PROCEEDINGS

OF THE

ROYAL SOCIETY OF LONDON.

From November 18, 1880, to March 17, 1881,

VOL. XXXI.

OCT 18 1881

LONDON :

HARRISON AND SONS, ST MARTIN'S LANE,, printers in (ftrbinarg to Witt IJtajtstg. MDCCCLXXXI.

LONDON :

HARRISON AND SONS, PRINTERS IN ORDINARY TO HER MAJESTY,

ST. martin's LANE

CONTENTS.

VOL. XXXI.

~+iH* No. 206.

Page

Researches on the Action of Organic Substances on the Ultra-Violet Rays of the Spectrum. Part III. An Examination of Essential Oils. By W. N. Hartley, E.R.S.E., &c, Professor of Chemistry in the Royal College of Science for Ireland, Dublin, and A. K. Huntington, F.C.S., Associate of the Royal School of Mines.., 1

Researches into the Colouring Matters of Human Urine, with an Account of the Separation of Urobilin. By Chas. A. MacMunn, B.A., M.D 26

No. 207.— November 18, 1880.

On the Essential Properties and Chemical Character of Beryllium (Gluci- num). By L. F. Nilson and Otto Pettersson '. 37

On the Molecular Heat and Volume of the Rare Earths and their Sul- phates. By L. F. Nilson and Otto Pettersson 46

On the Absorption Spectra of Cobalt Salts. By W. J. Russell, Ph.D., F.R.S., Treas. C.S., Lecturer on Chemistry at the Medical School, St. Bartholomew's Hospital 51

On the Friction of Water against Solid Surfaces of Different Degrees of Roughness. By Professor W. C. Unwin, M.I.C.E., Professor of Hy- draulic Engineering at the Royal Indian Engineering College 54

November 25, 1880.

On the Chemical Composition of Aleurone-Grains. By S. H. Vines, M.A., D.Sc, Fellow of Christ's College, Cambridge 59

On the Ossification of the Terminal Phalanges of the Digits. By F. A. Dixey, B.A. (Oxon.) (Plates 1, 2) 63

On a Sun-Spot observed August 31, 1880. By J. N. Lockyer, F.R.S 72

On Methods of Preparing Selenium and other Substances for Photo- phonic Experiments. By Professor Graham Bell 72

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November 30, 1880. Anniversary Meeting.

Page

Eeport of Auditors 73

List of Fellows deceased since last Anniversary 73

elected 74

Address of the President 74

Presentation of the Medals 95

Election of Council and Officers 101

Financial Statement : 103-105

Trust Funds 106-109

Account of Grants from the Donation Fund in 1879-80 110

Account of the Appropriation of the sum of .£1,000 (the Government Grant) annually voted by Parliament to the Eoyal Society, to be employed in aiding the advancement of Science 110

Account of Appropriations from the Government Fund of £4,000 made by the Lords of the Committee of Council on Education, on the recom- mendation of the Council of the Eoyal Society Ill

Eeport of the Kew Committee 115

List of Presents 138

No. 208.— December 9, 1880.

On a Simplified Form of the Torsion-Gravimeters of Broun and Babinet. By Major J. Herschel, E.E., F.E.S., Deputy Superintendent, Great Trigonometrical Survey of India 141

Note on the Microscopic Examination of some Fossil Wood from the Mackenzie Eiver. By C. Schroter, Assistant at the Botanical Labora- tory of the Polytechnic Institution, Zurich 147

The Electrostatic Capacity of Glass. By J. Hopkinson, M.A., D.Sc, F.E.S 148

The Cochlea of the Ornithorhynchus platypus compared with that of ordinary Mammals and of Birds. By Urban Pritchard, M.D., F.E.C.S., Aural Surgeon of King's College Hospital 149

December 16, 1880.

On Actinometrical Observations made in India at Mussooree and Dehra in October and November, 1879. By J. B. N. Hennessey, F.E.S., Deputy Superintendent, Great Trigonometrical Survey of India 154

On the Critical Point. By William Eamsay, Ph.D., Professor of Chemistry in University College, Bristol 194

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Further Researches into the Colouring-matters of Human Urine, with an Account of their Artificial Production from Bilirubin, and from Hsematin. By Charles A. MacMunn, B.A., M.D 206

Note on the Determination of Magnetic Inclination in the Azores. By T. E. Thorpe, Ph.D., F.RS 237

On Heat Conduction in Highly Earefied Air. By William Crookes, F.RS 239

On the Thermo-Electric Behaviour of Aqueous Solutions with Platinum Electrodes. By G. Gore, LL.D., F.RS 244

Influence of Voltaic Currents on the Diffusion of Liquids. By G. Gore, LL.D., F.RS 250

Experiments on Electric Osmose. By G. Gore, LL.D., F.R.S 253

List of Presents 257

Microscopical Researches in High Power Definition. By G. W. Boyston- Pigott, M.A., M.D. Cantab., F.RS. (Plates 3, 4) 260

No. 209.— January 6, 1881.

Researches on the Minute Structure of the Thyroid Gland. By E. Cress- well Baber, M.B. Lond 279

Note to the Paper on the Structure of the Immature Ovarian Ovum in the Common Fowl and in the Rabbit. By E. A. Schafer, F.RS 282

Note on a Communication made to the Eoyal Society by Professor Roscoe, LL.D., F.E.S.. " On the Absence of Potassium in Protagon prepared by Dr. Gamgee." By J. L. W. Thudichum, M.D., F.RC.P. Lond 282

Preliminary Note on the Existence of Ice and other Bodies in the Solid State at Temperatures far above their ordinary Melting Points. By Thomas Carnelley, D.Sc, Professor of Chemistry in Firth College, Sheffield 284

On the Effects of Heat on the Chloride, Bromide, and Iodide of Silver, and on some Chlorobromiodides of Silver. By G. F. Eodwell, F.E.A.S., F.C.S., Science Master in Marlborough College 291

Phenomena of the Capillary Electroscope. By G. Gore, LL.D., F.E.S 295

Electric Currents caused by Liquid Diffusion and Osmose. By G. Gore, LL.D., F.RS 296

Additional Note to a Paper " On the Thermal Conductivity of Water." By J. T. Bottomley, Lecturer in Natural Philosophy, and Demonstrator in Experimental Physics in the University of Glasgow 300

January 13, 1881.

On the 48 Co-ordinates of a Cubic Curve in Space, woode, M.A., D.C.L., President RS

By William Spottis- 301

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How do the Colour-blind See the different Colours ? Introductory Re- marks. By Frithiof Holmgren, Professor of Physiology, University, Upsala ,.. 302

Action of an Intermittent Beam of Radiant Heat upon Gaseous Matter. By John Tyndall, F.R.S 307

January 20, 1881.

On Gravimeters, with special reference to the Torsion-Gravimeter de- signed by the late J. Allan Broun, F.R.S. By Major J. Herschel, R.E., F.R.S., Deputy-Superintendent of the Great Trigonometrical Survey of India .... 317

Experimental Researches into Electric Distribution as manifested by that of the Radicles of Electro]ytes. By Alfred Tribe, F.I.C., Lec- turer on Chemistry in Dulwich College , 320

On the Tidal Friction of a Planet attended by several Satellites, and on the Evolution of the Solar System. By G. H. Darwin, F.R.S. 322

On the Female Organs and Placentation of the Racoon {Procyon lotor). By M. "Watson, M.D., Professor of Anatomy, Owens College, Man- chester , 325

Further Note on the Minute Anatomy of the Thymus. By Herbert Watney, M.A., M.D. Cantab 326

January 27, 1881.

The Refraction Equivalents of Carbon, Hydrogen, Oxygen, and Nitrogen in Organic Compounds. By J. H. Gladstone, Ph.D., F.R.S 327

On certain Definite Integrals. No. 8. By W. H. L. Russell, F.R.S 330

Polacanthus Foxii, a large undescribed Dinosaur from the Wealden Formation in the Isle of Wight. By J. W. Hulke, F.R.S 336

On Harmonic Ratios in the Spectra of Gases. By Arthur Schuster,

Ph.D., F.R.S 337

Dielectric Capacity of Liquids. By J. Hopkinson, F.R.S 347

Note on the Occurrence of Ganglion Cells in the Anterior Roots of the Cat's Spinal Nerves. By E. A. Schafer, F.R.S 348

On the Iron Lines widened in Solar Spots. By J. Norman Lockyer, F.R.S 348

List of Presents 350

No. 210.— February 3, 1881.

Upon the Cause of the Striation of Voluntary Muscular Tissue. By John Berry Haycraft, M.B., B.Sc, F.R.S.E., Senior Physiological Demon- strator in the University of Edinburgh. (Plate 5) 360

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cama

Description of some Eemains of the Gigantic Land-lizard (Megalc prisca, Owen) from Australia. Part III. By Professor Owen, C.B., F.B.S., &c , 380

On a Method of Destroying the Effects of slight Errors of Adjustment in Experiments of Changes of Eefrangibility due to Eelative Motions in the Line of Sight. By E. J. Stone, F.B.S., Director of the Eadcliffe Observatory, Oxford 381

On an Improved Bimodular Method of computing Natural and Tabular Logarithms and Anti-Logarithms to Twelve or Sixteen Places with very brief Tables. By Alexander J. Ellis, B.A., F.E.S., F.S.A. 381

On the Potential Eadix as a Means of Calculating Logarithms to any Ee- quired Number of Decimal Places, with a Summary of all Preceding Methods Chronologically Arranged. By Alexander J. Ellis, B.A., F.E.S., F.S.A 392

On the Influence of Temperature on the Musical Pitch of Harmonium Eeeds. By Alexander J. Ellis, B.A., F.E.S., F.S.A 413

February 10, 1881.

On the Influence of the Molecular Grouping in Organic Bodies in their Absorption in the Infra-red Eegion of the Spectrum. By Captain W. de W. Abney, E.E., F.E.S., and Lieutenant-Colonel Festing, E.E 416

Experiments undertaken during the Summer, 1880, at Yvoire (1,230 feet), Courmayeur (3,945 feet), and the " Col de Geant" (11,030 feet), on the Influence of Altitude upon Eespiration. By William Marcet, M.D., F.E.S 418

On a New Seismograph. By J. A. Ewing, B.Sc, F.E.S.E., Professor of Mechanical Engineering in the University of Tokio, Japan 440

February 17, 1881.

On the Viscosity of Gases at High Exhaustions. By "William Crookes,

F.E.S , 446

Note on the Eeduction of Mr. Crookes's Experiments on the Decrement of the Arc of Vibration of a Mica Plate oscillating within a Bulb con- taining more or less rarefied Gas. By Professor G. G. Stokes, Sec. E.S. 458

Notes on the Earthquakes of July, 1880, at Manila. By Commander W. B. Pauli, E.N., Her Britannic Majesty's Consul at Manila 460

February 24, 1881.

On a Simple Mode of Eliminating Errors of Adjustment in Delicate Ob- servations of Compared Spectra. By Professor G. G. Stokes, Sec. E.S. 470

Notes on Physical Geology. No. VII. On the Secular Inequalities in Terrestrial Climates depending on the Perihelion Longitude and Eccentricity of the Earth's Orbit. By the Eev. Samuel Haughton, Professor of Geology in the University of Dublin 473

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Further Experiments on the Action of an Intermittent Beam of Eadiant Heat on Gaseous Matter. Thermometric Measurements. By J. Tyndall, F.R.S 478

List of Presents 479

No. 211.— March, 3, 1881.

List of Candidates for Election 485

Some Experiments on Metallic Reflexion. No. II. By Sir John Conroy, Bart., M.A , 486

On the Trichophyton tonsurans (the Fungus of Ringworm). By George Thin, M.D 501

On Bacterium decalvans : an Organism associated with the Destruction of the Hair in Alopecia areata. By George Thin, M.D 502

On the Absorption of Pigment by Bacteria. By George Thin, M.D 503

On Toroidal Functions. By W. M. Hicks, M.A., St. John's College, Cambridge 504

Microscopical Researches in High Power Definition. Preliminary Note on the Beaded Villi of Lepidopt era- Scales as seen with a Power of 3,000 Diameters. By Dr. Royston-Pigott, F.R.S 505

March 10, 1881.

On the Conversion of Radiant Energy into Sonorous Vibrations. By William Henry Preece 506

On the Limit of the Liquid State. By J. B. Hannay, F.R.S.E 520

On the Diastase of Kdji. By R. W. Atkinson, B.Sc. (Lond.), Professor of Analytical and Applied Chemistry in the University of Tokid, Japan 523

March 17, 1881.

On the Electrical Resistance of Thin Liquid Films, with a Revision of Newton's Table of Colours. By A. W. Reinold, M.A., Professor of Physics in the Royal Naval College, Greenwich, anol A. "W. Riicker, M. A., Professor of Physics in the Yorkshire College, Leeds 524

Molecular Electro-Magnetic Induction. By Professor D. E. Hughes, F.R.S 525

On the Action of Sodium upon Chinoline. By C. Greville Williams, F.RS 536

List of Presents 541

Index 547

LX

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Obituary Notices :

David Thomas Ansted i

William Hallowes Miller ii

William Lassell vii

William Sharpey x

John Stenhouse xix

Humphrey Lloyd xxi

OBITUARY NOTICES OF FELLOWS DECEASED.

David Thomas Ansted was born in London on the 5th February, 1814, and after education at a private school, entered the University of Cam- bridge as a member of Jesus College. He was 32nd Wrangler in the year 1836, and proceeded to the degree of M.A. in due course. About four years afterwards he was elected to a fellowship on the Ley Foun- dation in his College, which he retained for about eight years. In 1840 he was elected Professor of Geology at King's College, London, which office he resigned in 1853. He was also for some time Lecturer on Geology at Addiscombe, and Professor of Geology at the College of Civil Engineers, Putney. From 1844 to 1847 he was Vice- Secretary of the Geological Society, of which he became a Fellow in 1838. He was elected to the Fellowship of the Royal Society in 1844.

By degrees his attention became diverted from the theoretic to the practical aspect of his favourite study, and for the last thirty years at least of his life he acted professionally as a consulting geologist and mining engineer. For some time before his death he was in failing health, and he expired on the 13th May, 1880, at his residence, Melton, near Woodbridge, Suffolk.

Professor Ansted, however, when systematic teaching ceased to be a part of his regular duties, did not abandon his interest in geology as an educational subject, but not unfrequently lectured and took part in examinations on this and allied sciences. His pen also was rarely for long idle. Besides some contributions to the " Quarterly journal of the Geological Society," the " Transactions of the Cambridge Philo- sophical Society," the " Annals and Magazine of Natural History," and other like publications, he was whole or part author of a con- siderable number of volumes ; the majority of these were of a some- what popular character, and more than one obtained a considerable share of success. He wrote lucidly and pleasantly whether upon matters more directly scientific or upon the incidents of travel. Among these works may be mentioned the following: "Geological Gossip," first published in 1860; "A Short Trip to Hungary and Transylvania," in 1862 ; " The Ionian Islands," in the year 1863 ; and " The Great Stone Book of Nature," published in the same year. He also published a work on geology, in two volumes, in 1 844, and more than one smaller book on this subject, physiography, or geography. He was joint author (with Mr. R. G. Latham) of a work on " The

I

II

Channel Isles," and wrote, in 1866, npon the " Physical Geography and Geology of Leicester." In the Great Exhibitions of 1851 and 1862 he contributed to the " Reports." His latest and one of his most im-. portant works was on " Water and Water Supply," published in 1878. Though for several years, owing to pressure of business and the advance of age, he had ceased to take an active part in the proceedings of the scientific societies of which he was formerly an energetic member, he did not lose that cordiality of manner and kindliness of disposition, which have left a pleasant impression on the memory of his friends.

William Hallowes Miller was born, April 6, 1801, at Velindre, near Llandovery, in Carmarthenshire. At this pretty spot, on the upper part of the strath of the Towey, his father, Captain Miller, had a few years previously fixed his residence. The associations of the family were essen- tially military. Captain Miller served through a part of the American War ; his house was burnt by the rebels, and he was in other respects a heavy loser. All the family papers were destroyed in this conflagra- tion ; but Captain Miller is believed to have been a descendant of a distinguished officer who was Adjutant- General to General Wolfe. He was twice married. Of his family by the first wife, two sons were killed in action one in the act of leading a storming party; another, though crippled by wounds, lived to be a Lieutenant- Colonel, and to receive the distinction of C.B. His daughter also married an officer in the Artillery. Captain Miller, after his return to England, and comparatively late in life, for he was then full sixty years of age, married the daughter of a Welsh clergyman. She was the mother of William Hallowes Miller, and died a few days after his birth.

After receiving his earlier education at private schools, he proceeded to St. John's College, Cambridge, and in the year 1826 graduated, being fifth among the Wranglers in the Mathematical Tripos. In the earlier part of 1829 he was elected a Fellow of his College, and pro- ceeded in due course to the degree of M. A. For some time he filled the office of a College tutor, and his first literary work was mathematical— a " Treatise on Hydrostatics," published in 1831, and followed a few years subsequently by one on " Hydrodynamics." The two were after- wards republished in one volume, and formed for many years the chief text-book on that subject in the Cambridge lecture-rooms. This treatise is conspicuous for its exactness and lucidity, though its terse- ness— a distinguishing feature in all the author's writings makes it a rather difficult book for a student of only average ability. At this time, the Chair of Mineralogy at Cambridge was occupied by Dr. Whewell, who, on his election to that office in the year 1828, had thrown himself energetically into its duties, and had especially de-

iii

voted himself to the study of crystallography. Miller was attracted to the same subject ; and four years later, when Professor Whewell ^resigned, he used his influence to obtain the chair for his pupil. Thus, in the year 1832, Miller was elected to the post, the duties of which became the chief work of his long and laborious life.

In 1838 Professor Miller was elected a Fellow of the Royal Society. In 1841 he proceeded to the degree of Doctor of Medicine. To this temporary diversion from more congenial studies he was compelled by the statutes which at that time governed the College. These required that all the Fellows, after a certain time, should be in Holy Orders, with the exception of four, two of whom were to be students of medicine. To one of these Fellowships Professor Miller was transferred in the year 1834; but it is needless to add that, though he complied with the requirements of the statute, he made no attempt to follow medicine as a profession. In 1844 he vacated his Fellowship at the College, by marriage, in accordance with the existing statutes. However, thirty years afterwards he was again elected a Fellow of his old College, under the statute (granted in 1860) em- powering the Society to elect as Fellows persons eminent for science or learning, though in other respects technically disqualified. But Professor Miller's work was now drawing near its end. From his youth he had been a hard worker, and had lived perhaps almost too sparingly. He delivered his lectures as usual in the earlier part of 1876, but a change in the expression of his face began to be rather marked, which seemed to forebode a giving way of his robust constitu- tion, and caused anxiety to his friends. Their fears were not ground- less. In the October term of 1876 a short course of lectures which he had announced was interrupted by a slight stroke of paralysis. This proved the beginning of the end. He was never able to meet his class again, and the duties of the chair were henceforth discharged by a deputy. Very slowly, but very surely, his vital powers declined a torpor stealing alike over mind and body till at last he fell asleep on the 20th May of the present year (1880).

Professor Miller's name is inseparably connected with two important branches of scientific work. The first of these belongs, as might be expected, to mineralogy. "Crystallography," as it has been said, " was Miller's science. It had taken its first shape in the hands of Haiiy in the decade of years before he was born, and in those of Weiss, of Mohs, and especially of Franz Ernst Neumann and of Grassmann ; it had been receiving development during the years of Miller's youth and manhood." To this his predecessor, Professor Whewell, had con- tributed by an important memoir on the geometrical treatment of crystal forms, published in the " Transactions of the Cambridge Philosophical Society." u Taking this memoir and Neumann's treatise of 1823 ('Beitrage zur Krystallonomie ') as his starting point,

IV

Miller proceeded to develop a system of crystallography, which was not published till 1838, but which was the most important work of his life." His system represented the face of a crystal by a symbol composed of three numerals, or indices. Selecting three crystallo- graphic axes, parallel respectively to possible edges of a crystal, and a face of that crystal making certain intercepts on these axes, and taking the three simplest whole numbers (a, b, c, suppose) whose ratio expressed the ratio of these intercepts, he expressed the ratio of the intercepts of any other face of the crystal, by multiplying a, b, c

respectively by i LI respectively, where h, h, I were integers, and

formed the symbol of the new plane.

"The elegant way" (to continue the words of Professor Maskelyne, already quoted) " in which this mode of representing a face lent itself to yielding expressions for the relations between faces belonging to a zone (i.e., faces that would intersect in edges parallel to the same line) gave it a superiority over previous methods, due to its bringing the symbols of the crystallographer into a form similar to that employed in algebraic geometry. Miller's work consisted in working out into a beautiful system the indicial method of notation and calculation in crystallography, and obtaining expressions adapted for logarithmic calculations by processes of great elegance and simplicity. Miller's system, then, gave expressions for working all the problems that a crystal can present, and it gave them in a form that appealed at once to the sense of symmetry and appropriateness of the mathema- tician." He thus, as it has been well said, " placed the keystone into the arch of the science of crystallography," and the " future develop- ment of that science, there can be little doubt, will follow on the lines laid down by Miller."

Professor Miller's shorter communications, on mineralogy and physics are numerous and valuable, and, in addition to them and to his original treatise, he published, in 1863, a tract on crystallography. In 1852 a work appeared entitled a new edition of the " Elementary Introduction to Mineralogy, by the late William Phillips," by H. J. Brooke and W. H. Miller. It is, however, no disparagement to either the original author or his fellow editor to say that Professor Miller made this volume almost his own. As has been said by the authority quoted above, " The publication of this severe little volume was an epoch in the science which it illustrated ; it contained a mass of results obtained by Miller with all his accuracy and all his patience through many years, and tabulated in his usual concise manner. It is a monument to Miller's name, though he almost expunged that name from it."

But Professor Miller's reputation does not rest only upon his work as a mineralogist, great though that was. His name is no less in-

separably connected with the difficult and delicate experiments and investigations connected with the restoration of the standards of measurement and weight, and with the subsequent labours of the International Metric Commission.

After the fire which, in 1834, consumed the Houses of Parliament, it was found that the standards of measurement and weight there preserved were hopelessly ruined, and a Commission was appointed to consider the questions connected with their restoration. Professor Miller was not, indeed, a member of that Commission, but it is well known that his friendly assistance contributed greatly to guide the Commission in some of their more important recommendations, espe- cially in those which related to the means to be provided for con- tingent restoration of the standard of weight. In sections 3 and 5 of the Act 5th George IY, it was directed that "in case of the loss of the standard, the yard shall be restored by taking the length which shall bear a certain proportion to the length of the pendulum, vibrat- ing seconds of mean time in the latitude of London, in a vacuum, at the level of the sea; and that the pound shall be restored by taking the weight which bears a certain proportion to the weight of a cubic inch of water weighed in a certain manner." In their report, dated December 21, 1841, the Commissioners decline to recommend the adoption of these provisions, for reasons which are given therein, and advise that each standard should be restored from measures and from weights then existing, which had been most care- fully compared with the original standards, stating also that they were " fully persuaded that, with reasonable precautions, it may always be possible to provide for the accurate restoration of standards by means of material copies, which have been carefully compared with them, more securely than by reference to experiments referring to natural constants."

In 1843 a Committee was appointed to superintend the construction of the new Parliamentary standards of length and weight, of which Professor Miller was a member, and to him was confided the construc- tion of the new standards of weight. In the " Philosophical Trans- actions " for 1856 he describes at length " The operations for restoring the value of the Old Standard of Weight, for constructing the New Standard of a different value, for constructing various derived Stan- dards, and for establishing the relative value of the Kilogramme," a paper which (to quote the words of the Astronomer Royal, endorsed by a former President of this Society, Sir Edward Sabine) " will long be cited as a model of accuracy."

He was subsequently a member of a new Royal Commission for " examining into and reporting on the state of the secondary standards, and for considering every question which could affect the primary, secondary, and local standards."

VI

In the year 1870 he was appointed a member of the Commission. Internationale dn Metre. This led to various visits to Paris between the above year and 1874. More than one of his colleagues has ex- pressed in the warmest terms his sense of the value of Professor Miller's services to that Commission. Perhaps there was no member whose opinions had greater weight in influencing a decision upon any intricate and difficult question.

His services to this Society must not be forgotten in a sketch of his life, however brief. Elected a Fellow in the year 1838, he was appointed Foreign Secretary in 1856, a post for which he was emi- nently fitted by his accurate and extensive knowledge of French, German, and Italian, his methodical habits, and unvarying courtesy, as well as by his extensive scientific knowledge.

To those who enjoyed Professor Miller's friendship three charac- teristics were conspicuous above all. One was the extent and the accu- racy of his knowledge. Not only on those subjects to which he had more notably devoted himself, but on almost any question of physical science he was an authority. Younger men in Cambridge looked upon him as a kind of living encyclopaedia, for their questions were at once met by answers, clear, accurate, and concise. As one of tbe most competent judges now living in that University writes, " There was, I think, no person in Cambridge whose knowledge of natural philosophy on the whole exceeded, or even equalled, that of Professor Miller. He kept up his reading to an extent that was surprising."

Another was the simplicity of his disposition. Seldom has there been a man with so few wants. To all except himself he was generous ; hospitable to his friends, he was almost Spartan in his own habits. This trait combined with the remarkable inventiveness of his mind, is evidenced even in his laboratory. There the visitor is surprised to find the most homely odds and ends utilised in the construction of instru- ments capable of performing delicate measurements. " Give Professor Miller," a friend has said, " some loose lenses, bits of glass tubing, laths, copper wire, and especially some pill-boxes, and he will make any instrument that he wants."

The third characteristic was the remarkable combination which he exhibited of independence of thought and freedom of opinion, with gentleness of temper and speech, with forbearance, courtesy, and respect for the opinion of others. No one, however conscious of infe- riority, whether in experience or in mental powers, had any reason to fear to speak in the presence of Professor Miller. His words were sure to be received with consideration, often almost with deference, beyond their deserts.

His life's course was tranquil and full of quiet happiness. Until his last illness he enjoyed excellent health. Tear after year was spent in the labours to him a pleasure which have been briefly noticed, with

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an occasional visit to the Continent, either for duty or for relaxation. He delighted especially in the scenery of the dolomite mountains of the Italian Tyrol, spending among them many hours of quiet enjoy- ment, while their magnificent outlines were recorded with rare fidelity by the accomplished companion of his life.

Happy, then, in his domestic life, happy in the affectionate appre- ciation of numerous friends of varied ages and ranks, he was also happy in seeing his work (though for honours and rewards he cared less than most men) not unacknowledged by his contemporaries. In addition to the honours mentioned above, lie received in 1865 the degree of LL.D. from the University of Dublin, and in 1876 that of D.C.L. from Oxford. In 1870 he was awarded a Royal Medal by this Society. He was a Knight of the Order of St. Maurice and St. Lazare of Italy and of the Order of Leopold of Belgium. He was also an honorary member of the Royal Society of Edinburgh, of the Mineralogical Society of France, and of Boston, U.S.A., a foreign member of the Mineralogical Society of St. Petersburg, of the Imperial Royal Academy of Sciences, Vienna, and of the Royal Society, Got- tingen ; and a corresponding member of the Academies of Berlin, Munich, Paris, St. Petersburg, and of Turin.

William Lassell. LL.D., died at Maidenhead, October 5, 1880, aged eighty-two years. He was born at Bolton, Lancashire, June 18, 1799. He acquired the rudiments of education at a day school in his native town, during which time his father died, and thence went for eighteen months to an academy at Rochdale.

In 1814 he entered a merchant's office at Liverpool, and there served a seven years' apprenticeship. He commenced business in Liverpool as a brewer about the year 1825, without, however, much taste or inclina- tion for trade, and spent almost all his leisure time in his favourite pursuit of astronomy and the mechanics connected therewith.

Mr. Lassell possessed a great love and aptitude for mechanical invention, and for this reason " he belonged," to use the words of Sir John Herschel, " to that class of observers who have created their own instrumental means, who have felt their own wants, and supplied them in their own way." The qualities which enabled Mr. Lassell to do all this made him what he was. The work was the revelation of the man. He felt precisely where lay the difficulties and wants which met him in his work, because he was sensitive and sympathetic. He could deal successfully with these difficulties and supply these wants often in a masterly and original way, because he could think for himself cautiously yet boldly. He could work out his conceptions in new and difficult directions to a successful issue, because the constancy of his character showed itself here in concentration of thought and perseverance of

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action. These qualities sensitive sympathy, wise prudence, constancy were those which pre-eminently characterised him as a man, and made him to those who knew him a friend of rare worth .

In the history of science Mr. LasseU's name will rank with those of Herschel and the late Lord Rosse in connexion with that essentially British instrument, the reflecting telescope, whether we consider the genius and perseverance displayed in the construction of these instru- ments or the important discoveries which have resulted from their use. About 1820 Mr. Lassell, then in his twenty-first year, began to con- struct reflecting telescopes for himself. It is perhaps to circumstances which he at the time considered unfavourable, that science is indebted for much that Mr. Lassell has accomplished. At that time he did not pos- sess sufficient means to enable him to purchase expensive instruments, and besides "his business avocations were such as most men consider of an engrossing nature." The value to him in his subsequent work of the energy and power of resource which were in this way so strongly developed in his character at an early age, it is difficult rightly to appraise. His success with the first two instruments, which he attempted simultaneously (a Newtonian of seven inches diameter and a Gregorian of the same size), encouraged him to make a Newtonian of nine inches aperture. The instrument, which was erected in an observa- tory at his residence near Liverpool, happily named Starfield, may be said to form an epoch in the history of the reflecting telescope, in conse- quence of the successful way in which Mr. Lassell, on a plan of his own, secured to it the inestimable advantages of the equatorial move- ment. The several mirrors made for this instrument were of great excellence. The observatory note-books of the late Mr. Dawes, which are in the writer's possession, bear record to the delicate tests for figure to which these mirrors were put on the occasions of the frequent visits of Mr. Dawes to his friend's observatory. With this instrument Mr. Lassell diligently observed, and detected, without knowledge of its existence, the sixth star in the trapezium of the nebula of Orion. This instrument is fully described in the twelfth volume of the " Memoirs of the Royal Astronomical Society."

About the year 1844 Mr. Lassell conceived the bold idea of con- structing a reflector of two feet aperture and twenty feet local length, to be mounted equatorially on the same principle. He spared neither pains nor cost to make this instrument as perfect as possible, both optically and from the mechanical side. As a preliminary step, he visited the late Earl of Rosse at Birr Castle, and commenced the specula for the new instrument upon a machine similar in construction to that employed by that noKleman. After some months' work, he was not satisfied with this apparatus, and was led in consequence to contrive a machine for imitating as closely as possible those motions of the hand by which he had been accustomed to produce perfect surfaces on

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smaller specula. " The essential difference of these constructions," to nse the words of Sir George Airy, " as regards the movements of the grinder is this : that in Lord Rosse's apparatus every stroke is very nearly straight, while in Mr. Lassell's apparatus there is no resem- blance to a straight movement at any part of the stroke." This is not the place to describe the many new contrivances in the mode of support of the mirror, in the equatorial mounting, in the polishing machine, and in the arrangements of the dome under which it was erected, which enabled Mr. Lassell to bring his telescope to a high degree of perfection. In this connexion it should be noticed, to use Sir John Herschel's words, " that in Mr. Nasmyth he was fortunate to find a mechanist capable of executing in the highest perfection all his concep- tions, and prepared by his own love of astronomy and practical acquaintance with astronomical observations, and with the construction of specula, to give them their full effect."

With this fine instrument he discovered the satellite of Neptune. This minute body was seen on October 10th, 1846, but it was not until the next year that it could be satisfactorily followed, and its existence fully confirmed. The superiority of the telescope, and the vigilance and skill of the observer were further shown by the discovery in 1848, simultaneously with Professor Bond in America, of an eighth satellite of Saturn, of extreme minuteness, which was named Hyperion. In 1851, after long and careful search, he discovered two additional satellites of the planet Uranus (Umbriel and Ariel), interior to the two discovered by Sir William Herschel in 1787.

In the autumn of 1852, he took this twenty-foot telescope to Malta, and observed with it there through the winter. A very care- ful and detailed drawing of the nebula of Orion, and drawings of several planetary nebulas made at Malta, will be found in vol. xxiii of the " Memoirs of the Royal Astronomical Society." With respect to the planets, his discoveries, to use his own words, " were rather negative than otherwise," for he was satisfied, that without great increase of optical power, no other satellite of Neptune could be detected. With regard to Uranus, he says, " I am fully persuaded that either he has no other satellites than the four, or if he has, they remain yet to be discovered."

Mr. Lassell's energy and zeal in the cause of science did not permit him to remain content with this magnificent telescope. His last work was a much larger telescope, four feet in aperture, and thirty-seven feet focus, mounted equatorially, which was erected at Malta, in 1861. The work done with it, with Mr. Marth's as- sistance, during the next four years, is fully described, as well as the instrument itself, in vol. xxxvi of the " Memoirs of the Royal Astro- nomical Society." This work consists of numerous observations of nebulas and planets, and a catalogue of the places of 600 new nebulas

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discovered at Malta. It is not possible to suppress a feeling of regret that this grand instrument no longer exists.

Mr. Lassell was very successful in the great brilliancy and perma- nence of polish of his mirrors. Within the last few years the writer has been shown specula by Mr. Lassell, which had been polished for more than twenty years, and which appeared as bright as if but just removed from the polishing machine. His earlier metal differed from that employed by Lord Rosse, in that it contained a small quantity of arsenic in addition to copper and tin. In the case of his four-foot mirrors, the arsenic was omitted. He seems to have considered that the perfection of the metal depended upon the accurate relative pro- portion of the copper to the tin, and that, in consequence of the uncertainty of the state of purity of the metals, this proportion would be obtained with the necessary accuracy only by a series of testings, while the metal was in the pot.

After his return from Malta, Mr. Lassell purchased a residence near Maidenhead, and erected there in an observatory, his equatorial tele- scope of two-foot aperture. Mr. Lassell's experience in re-polishing his four-foot mirror, suggested to him some alterations in his polishing machine. After his return, he was able to carry out experiments in connexion with the suggested alterations in a workshop erected at Maidenhead, and succeeded in constructing an improved form of polishing machine, which is described in the " Philosophical Transac- tions" for 1874. The numerous papers by Mr. Lassell, to be found in the " Monthly Notices," and the " Memoirs " of the Royal Astronomical Society, bear abundant record to his industry and skill, and make us feel that in Mr. Lassell's death we have to deplore the loss of one who contributed largely to the advancement of the science of his age.

Mr. Lassell was elected a Fellow of the Royal Astronomical Society in 1839, he received the Gold Medal of that Society in 1849, and in 1870 was elected its President, which office he held for two years. He became a Fellow of the Royal Society in 1849, and received one of the Royal Medals in 1858. Among other honours conferred upon him, may be mentioned an honorary degree from the University of Cambridge, and the honorary Fellowship of the Royal Society of Edinburgh, and of that of Upsala.

Dr. William Shaepey was born at Arbroath, in Forfarshire, Scot- land, on the 1st of April, 1802. His father was an Englishman and belonged to Folkestone, in Kent, till the year 1794, when he migrated to Arbroath, and there married Mary Balfour, a native of that place ; but, he dying shortly before the birth of his son William, Mrs. Sharpey was afterwards married to Dr. William Arrott, a medical practitioner of Arbroath, in whose family the subject of this notice was brought up.

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William Sharpey's education was carried on up to the age of fifteen at the public school of Arbroath. In November, 1817, he entered the University of Edinburgh as a student in the Faculty of Arts, attending the Greek and Natural Philosophy classes.

In 1818 he commenced his medical studies, in the University and the extra- academical school of Edinburgh. In the latter school his teacher in anatomy was Dr. John Barclay, well known for his energy as a writer and lecturer and his ingenuity as an observer in human and comparative anatomy. In chemistry his chief instructor was Dr. John Murray, of whose scientific accuracy and judgment Dr. Sharpey always spoke in the warmest terms. In 1821, at the age of nineteen, he obtained the diploma of the Edinburgh College of Surgeons. He then passed some months of that year in the study of anatomy at Brookes' School in London, and in the autumn proceeded to Paris and remained there for nearly a year, in attendance upon the medical and surgical wards of the hospitals, more especially in the surgical wards of the Hotel Dieu, under the instruction of the celebrated Dupuytren. In Paris he had the com- panionship of his friend Dr. Robert Willis, and he first made the acquaintance of Professor Syme, with both of whom he was ever after on the most intimate and friendly terms.

In August, 1823, he took the degree of Doctor of Medicine in the University of Edinburgh, his printed inaugural dissertation bearing the title "De Yentriculi Carcinomate ;" and in the latter part of the year he went again to Paris to complete his studies in medicine and surgery at the hospitals, and in natural history at the Garden of Plants. After his return from France in the summer of 1824, his plans seem to have remained for some time undecided until near the end of 1826, when he finally resolved not to embark in medical practice, but to devote himself to anatomical and physiological pur- suits, for which he had long had a predilection, and to the study of which he had already given a considerable share of attention.

With this view he resolved upon completing his continental travels, and obtaining the advantages of study in the Italian and German schools, as he had already done very fully in the French ; and accordingly, in the autumn of 1827, he proceeded by way of Paris and Geneva to Switzerland, in which he made a three months' pedestrian tour. He then travelled in the north of Italy, visiting Milan, Pavia (where he spent some time in company with Panizza), Genoa, and Florence. The winter was passed in Rome, Naples, and other places of interest in central Italy ; and in the spring of 1828 he turned his steps northward, taking the way of Bologna, Padua, and Venice, to Verona and Innsbruck. The summer was spent in Austria and North Germany, and he finally reached