PROCEEDINGS OP THE LITERARY AND PHILOSOPHICAL SOCIETY OF MANCHESTER VOL. V. Session 1865-66. MANCHESTER : PRINTED BY TITOS. SOWI.ER AND SONS, ST. ANN’S SQUARE. LONDON : H. BAIT. LI ERE, 219, REGENT STREET. 1866. NOTE. The object -which the Society have in view in publishing their Proceed- ings, is to give an immediate and succinct account of the scientific and other business transacted at their meetings, to the members and the general public. The various communications are supplied by the authors them- selves, who are alone responsible for the facts and reasonings contained therein. INDEX. Ainsworth Thomas. — On a Predisposing Cause of Cattle Disease, p. 21. AlC'OCK Thomas, M.D. — Questions regarding the Life History of the Fora- minifera, suggested by Examinations of their Dead Shells, p. 15. Foraminifera from Dogs Bay, p. 99. On Foraminifera from a Shell of Halia Priamus, p. 123. Embryonic Shells of Mollusca, p. 166. Bates Rev. J. C., M.A., F.R.A.S. — Results of Rain Grange and Anemometer Observations made during the year 1865, at St. Martin’s Parsonage, Castleton Moor, p. 168. Baxendell J., F.R.A.S., Hon. Sec. — Auroral Phenomena, October 19 and 26, 1865, p. 15. On a Probable Cause of the Cattle Disease, p. 21. Note on the Variable Star S Delphini, p. 28. On Meteors, p. 59. Note on the Variable Star T Aquihe, p. 88. Cattle Plague, p. 91. Storm Warnings in India, p. 101. Note on the Variable Star S Corona;, p. 109. On the Determination of the Mean Form of the Light-Curve of a Variable Star, p. 112. On the Fall of Rain during the Different Hours of the Day, as deduced from a series of Observations made by the Rev. J. C. Bates, M.A., F.R.A.S., at St. Martin’s Parsonage, Castleton Moor, p. 129. New Variable Star R Crateris, p. 191. Binney E. W., F.R.S., F.G-.S., V.P. — On the Difficulties of Working Deep Coal Mines, p. 12. On Fossil Wood found in calcareous nodules in the lower coal seams of Lancashire and Yorkshire, p. 61. On Fossil Wood in calcareous nodules found in the Upper Foot Coal, near Old- ham, p. 113. On a singular Mineral found in a nodule of clay iron- stone from the North Staffordshire coal field, p. 147. On the Humming-bird Hawk Moth, p. 161. Bottomley J. — On the Probable Effect of the Exhaustion of the Coal Fields upon the Condition of the Atmosphere, p. 45. 'Brockbank W. — Notes on a Section of Chat Moss, near Astley Station, p. 91. On the Liassic and Oolitic Iron Ores of Yorkshire and the East Midland Counties, p. 119. VI Brothers A., F.R.A.S. — Photographs of the Eclipse of the Moon, Oct. 4, 1865, p. 3. On Celestial Photography, p. 68. On Mr. Rogerson’s Method of Cleaning Glass Plates, p. 134. On an Experiment Illus- trating the Appearances of Sun Spots, p. 171. On a Meteoric Body Crossing the Moon’s Disc, p. 172. Note on the First Use of Hypo- sulphite of Soda in Photography, p. 181. Clifton Prof. R. B., M.A., F.R.A.S. — An Attempt to Refer Some Pheno- mena Attending the Emission of Light to Mechanical Principles, p. 24. Cockle Chief Justice, M.A., F.R.A.S., F.C.P.S. — On Coresolvents, p. 13. Dancer J. B., F.R.A.S. — On the Eclipse of the Moon, Oct. 4, 1865, p. 9. Illumination of Opaque Objects under the High Powers of the Micro- scope, pp. 31, 42, and 55. On the Boulton and Watt Pictures, p. 134, 157. Dickinson W. L. — Eclipse of the Sun, Oct. 19, 1865, p. 2. Eclipse of the Sun, Oct. 8, 1866, and Occupations of Aldebaran, Sept. 28 and Nov. 22, 1866, p. 170. Dyer J. C., Y.P. — Breaking of the Atlantic Cable, p. 1. Notes on the Origin of Several Mechanical Inventions, and their Subsequent Application to Different Purposes, Part I., p. 5 ; Part II., p. 48; Part III., p. 102. Notes on Cotton Spinning Machinery, Part II., Roving Frames, p.148. Greaves George, M.R.C.S. — On the Internal Heat of the Earth as a Source of Motive Power, p. 1. Hardy Mr. — On a Large Cetacean Vertebra found in the Valley of the Don, p. 32. Heelis Thomas, F.R.A.S. — On a Coal Basin between Mount Olympus and the Bay of Oraniska, p. 13. On Meteors, p. 58. Herschel Sir J. F. W., Bart., M.A., D.C.L., F.R.S., &c. — On a Method of Cooling the Workings of Deep Coal Mines, p. 11. Hull E., F.G.S. — The Raised Beach on the Coast of Cantyre, p. 13. On the Liassic and Oolitic Iron Ores of Yorkshire and the East Midland Counties, p. 119. Hurst H. A. — On late Improvements in Illuminating Opaque Objects under the Higher Powers of the Microscope, p. 64. Jbvons W. S., M.A. — On a Logical Abacus, p. 161. Johnson J. R. — On the Pantascopic Camera, p. 135. Vll Joule J. P., LL.D., F.R.S., V.P. — Camera for Outdoor Work without a Tent, p. 4. Effect of the Aurora of Oct. 19, 1865, on his Magnetic Needle, p. 15. Photographs of the Sun, p. 85. On a New Balance, pp. 145, 165. Knott George, F.R.A.S. — On the November Meteors, as observed at Wood- croft, Cuckfield, Susses, Nov. 12-13, 1865, p. 56. Light-curve of R Yulpeculse, p. 59. Results of Observations of T Aquilee, p. 90. On the Variable Star R Vulpeculse, p. 124. Results of a Comparison of the Magnitudes of the Bedford Catalogue with those of the Mensurse Micrometricse and the Bonner Sternverzeichniss, p. 187. Latham Arthur G. — On Two Beetles nearly Allied to Rhynchophorus Palmarum, p. 193. Linton James. — On the Humming-bird Hawk Moth, p. 105. Mackereth T., E.R.A.S. — Rainfall at Eccles for 1864, p. 10. Results of Rain Gauge and Anemometer Observations at Eccles during the year 1865, p. 107. Nasmyth James, C.E. — On the Casting, Grinding, and Polishing of Specula for Reflecting Telescopes, Part. I., p. 181. Parry John. — On Collecting Eoraminifera on the West Coast of Ireland, p. 42. Roberts W., M.D. — Injurious Effects produced by burning Pharaoh’s Ser- pents in Close Rooms, p. 33. Roscoe Prof. H. E., F.R.S., Hon. Sec. — Enlarged Photograph of the Moon by Mr. Rutherford, p. 1. Injurious Effects of inhaling Mercury Vapoiu’, p. 33. Meteorological Registration of the Chemical Action of Daylight, p. 96. On the Didymium Spectrum, p. 147. Sidebotham J. — Notes on Atlantic Soundings, p. 18. Notes ou Acherontia atropos, p. 19. Discovery of Apion ononis, a species of Curculio, in the Isle of Anglesey, p. 20. On the Application of Measuring Rods to Photographic Pictures, p. 67. Cement for Use in Mounting Fluid Preparations of Objects for the Microscope, p. 98. On the Boulton and Watt Pictures, p. 134, 150. Smith R. Angus, F.R.S., P. — Effect of Dews and Fogs in producing Epi- demics, p. 22. Abrasion of Iron Rails on Railways, p. 23. On Air from off the Atlantic, and from some London Law Courts, p. 115. via Sonstadt E. — Note on the Purification of Platinum, p. 117. Thorpe T. E. — On the Amount of Carbonic Acid contained in the Air above the Irish Sea, p. 33. Vernoh G-. V., F.R.A.S., M.B.M.S. — Remarks on the Barometric Disturb- ances during the Months of October, November, and December, 1865. p. 85. Rainfall for 1865, p. 87. Meetings of the Physical and Mathematical Section. — Annual, p. 124. Ordi- nary, pp. 9, 28, 56, 85, 107, 168, 187. Meetings of the Microscopical and Natural History Sections. — Annual, p. 193. Ordinary, pp. 18, 42, 64, 98, 105, 122, 166. Meetings of the Photographical Section. — Annual, p. 192. Ordinary, pp. 3, 67, 96, 134, 181. Report of the Council. — April 17, 1866, p. 173. PROCEEDINGS OF THE LITERARY AND PHILOSOPHICAL SOCIETY. Ordinary Meeting, October 3rd, 1865. Edward Schunck, Ph.D., F.R.S., &c., Vice-President, in the Chair. Dr. Roscoe exhibited an enlarged photograph of the moon, 21 inches in diameter, taken by Mr. L. M. Ruther- ford, of New York, on the 6th of March last. Mr. Brothers, Mr. Vernon, and other members, pronounced it to be the best lunar photograph they had seen, and decidedly superior to any yet producedfein this country. Mr. Dyer, referring to the breaking of the Atlantic Cable, expressed his surprise that no apparatus had been provided to seize and secure the end of the cable when the rupture took place, as contrivances for a similar purpose were in use in almost every cotton mill. A paper was read “ On the Internal Heat of the Earth as a Source of Motive Power,” by Mr. George Greaves, M.R.C.S. Proceedings — Lit. & Phil. Society. — Vol. Y. — No. 1. — Session 1865-6. 9. It has been very generally admitted that coal will not cease to be furnished because of the exhaustion of the stores of the mineral now existing in the coal measures ; and fur- ther, that the obstacles to the continued working of the mines will not be engineering difficulties. The increased depth from which the coal will have to be brought may add to the cost, but at that increased cost it will still be for a long time obtainable. The author considered the real insur- mountable obstacle to be the high temperature of the lower portions of the carboniferous strata. That temperature had been shown to be at a depth of 4,000 feet at least 120° Fahr., a degree of heat in which human beings cannot exist for any length of time, much less use any exertion. It had occurred to the author to inquire whether the very agency which will prevent the continued supply of fossil fuel might not be made the means of rendering that supply unnecessary — whether, in short, the internal heat of the earth might not to some extent be utilised. One or two modes of doing this had pre- sented themselves to his mind. One of these might, he con- ceived, be the direct production of steam power by bringing a supply of water from the surface in contact with the heated strata by means of artesian borings or otherwise. Mr. W. L. Dickinson read the following note on the eclipse of the sun which will take place on the 19th instant : Calculation for Manchester (Royal Infirmary), Lat. N. 53° 29', Long. W. 2° 14'. At Manchester a partial eclipse is partly visible, and • h. m. s. . Regins October 19th — 4 8 12 Greatest phase ...October 19th — 5 4 2 Greenwich mean time. At Manchester the sun will set at 6h. 2m. Greenwich mean time. 3 Magnitude of the eclipse (sun’s diameter = 1) 0*293, on the sun’s southern limb. Angle, from north pole, of first contact 120° Howards the Angle, from vertex, of first contact 1 53° ) west for direct image. The situation of the point of first contact may be familiarly illustrated in the following manner. If wre suppose a Victoria shilling to represent the sun, the moon will appear first to touch it on the right side near the bottom, at the letter D. PHOTOGRAPHICAL SECTION. October 5th, 1 865. J. P. Joule, LL.D., F.R.S., Vice-President of the Section, in the Chair. Messrs. Coote and Rogerson exhibited a series of very fine pantascopic photographs of scenes in Switzerland, taken by M. Adolphe Braun, of Dornach. Each picture was about twenty-one inches in length, and the angle of view was stated to be one hundred and twenty degrees. Mr. A. Brothers, F.R.. A.S., exhibited an interesting series of photographs, taken during the eclipse of the moon, on the evening of Wednesday, October 4th. Commencing at 8.45, when the moon was nearly full, the negatives, twenty in number, were taken at intervals of about 12 minutes until 12.45, and they show the progress of the eclipse throughout. The effect of the penumbral shadow of the earth is distinctly visible on the negative taken at 9.15, and also on the one taken at 12.32. An attempt was made during the middle of the eclipse to obtain the photographic image of the entire surface of the moon ; but it was found that the portion 4 covered by the earth’s shadow had no effect on the plate after an exposure of 1 5 seconds, although distinctly visible in the telescope. It was noticed that the southern limb of the moon showed the copper-coloured tint often seen during total lunar eclipses, and to this cause may be attributed the non-actinic effect on the sensitized plate. An exposure of about one or two tenths of a second gave the fully illuminated surface of the moon perfectly, but the parts covered by the penumbra were not defined, while an exposure of three seconds gave the outline of the earth's shadow with great distinctness, and an exposure of two seconds brought out some of the detail within the penumbra. Some of the negatives were obtained almost instantaneously. The telescope with which these pictures of the moon were taken is an equatorial of 5 inches aperture and 6 feet focal length, driven by clockwork. This telescope gives the image of the moon about Bths of an inch in diameter, but by using a Barlow’s lens this size is increased to inch, and with this addition the eighteenth negative of the series was obtained in two seconds. Dr. Joule, F.R.S., exhibited and explained the construc- tion of a camera which he had contrived for outdoor work without a tent. In this camera the operation was carried on by the succes- sive introduction of the sensitizing and developing baths, the mode of the application of the baths being similar to that already described by the author. By a special arrangement the holders of the plate are preserved from contact with the developing solution. 5 Ordinary Meeting, October 17th, 1865. E. W. Binney, F.R.S., F.G.S., &c., Vice-President, in the Chair. Mr. Forrest stated that he had in his possession a very extensive collection of Shakespeare memorials, which he would gladly allow any member of the Society to inspect. A paper was read entitled w Notes on the Origin of several Mechanical Inventions, and their subsequent application to different purposes,” by J. C. Dyer, V.P. lsif. — Lace Making Machine. The bobbin net trade at Nottingham had been carried on by women working on cushions or lace frames until about the beginning of this century, when the process was super- seded by the lace making machine, invented by the late Mr. John Heathcoat, M.P. Mr. Heathcoat commenced his ex- periments by stretching common packing threads across his room for the warp , and then passing, by common plyers, the weft threads between the cords, delivering them into other plyers on the opposite side, and then, after giving them a sideways motion, repassing the threads back between the next adjoining cords, and thus effecting the intersecting or tying of the meshes in the same way as they were formed on the cushions worked by hand. His next step was to provide thin metallic discs to be used as " bobbins ” for conducting * the thread back and forth through the warp. These discs being arranged in carrier frames, placed on each side of the Proceedings — Lit. & Phil. Society. — Vol. V.— No. 2. — Session 1865-6. 6 warps, were moved by suitable machinery so as to conduct the threads from side to side to form the lace. The limits of this abstract do not allow any detailed description of Mr. Heathcoat’s beautiful invention ; its effect, however, in super- seding the hand work appears to have led to the Nottingham riots and the lace frame breaking, which took place about fifty years ago, when Mr. Heathcoat removed to Tiverton in Devonshire, where the patent lace making was re-established, and has been since carried on upon a large scale, and has thus proved an eminently successful invention. The new principle of action conceived by Mr. Heathcoat was that of passing the threads of the weft through those of the warp and delivering them into conductors on the other side, to be repassed and delivered into the former conductors under mechanical control in place of hand working. He suc- ceeded in working out this principle with marvellous perse- verance and success, and this original conception of Mr. Heathcoat opened a new vista to other eminent mechanics, which led to the invention of many other valuable machines for widely different purposes, among which may be named that for passing back and forth the threads through fabrics for embroidering, as now exhibited in the beautiful machines for embroidering or ornamenting fabrics in the works of Messrs. Houldsworth. On the same principle is also based the cotton combing process now employed for separating the short and coarse from the long staples in fine cotton carding. 2nd. — Wire Card Making Machine. About the beginning of this century Mr. Amos Whitimore, of Boston, commenced his experiments for making cards by machinery. His first step was to examine the movements required to form and set card teeth for hand carding. He w'as for a long time engaged with trial machines, and ultimately succeeded in performing the operations for making 7 and setting the card teeth by movements effected by eccen- trics on a driving shaft, viz. (1) feeding the wire, (2) hold- ing it, (o) cutting off and (4) bending the wires into staples, (5) piercing holes in the leather, (6) passing the staples through it, (7) pressing their crowns to the sheet, (8) crook- ing the teeth to the knee bend, and (9) advancing the -leather to receive the next row of teeth. These complex and curious motions were effected by a series of cams or eccentric pieces fixed on the shaft and turned by a winch ; therefore the invention of making wire cards by machinery was accom- plished by Amos Whitimore, but it was many years thereafter before his machine could be made profitable in competing with the hand card makers. The final development of this invention is explained at large in the paper, but cannot be given in this abstract. In this machine, as in that of Mr. Heathcoat’s, a new principle of action Avas adopted to produce and govern the movements for making Avire cards, viz., that of eccentric curves revolving on a driving shaft and guiding the motions of the traversing parts of the machines in their due order of succession for making and setting the card teeth as before stated. This application of curvilinear projections or cam pieces has since been extensively employed for giving intricate motions in many other machines invented during the last fifty years. Whence it appears that both Mr. Heathcoat and Mr. Whiti- more became pioneers and guides to other able mechanicians in their several labours for the advance of mechanical science. Among the inventions based upon that of the carding machine may be mentioned the machine for making the eyes or shanks of metal buttons, the machine for making Avire reeds for weaving, and that for making pins. But without dAvelling on other instances, it Avill suffice to say that the success of the lace machine and that of the wire card machine serve to spread the seeds of knoAvledge in prac- tical mechanics, the germs of which, half a century ago, were 8 widely cast forth from the fertile geniuses of John Heathcoat and Amos Whitimore. 3rd. — Cutting Furs from Pelt. In the year 1810 a model fur cutting machine was sent to me in London by a company in Boston, to be patented in England. It was stated to be the invention of a Mr. Bellows, who was unknown to me. The machine was adapted for shearing fibres from surfaces by the action of spiral cutters revolving and acting against a fixed straight cutter, so as to shear or cut fibres from the surfaces to which they are attached. I had a machine made and put into operation at a hat manufactory in the Borough ; but the workpeople opposed its being used, which discouraged further attempts to bring it into use in that trade. The principle of it, how- ever, was soon after patented for chopping straw, roots, Sec., for which it was found valuable. Two or three patents were afterwards taken out for shearing the nap from cloth by the same action of spiral cutters revolving against a straight fixed edge, and many others have since appeared on the same principle, among which is that for mowing lawns. 9 PHYSICAL AND MATHEMATICAL SECTION. October 12th, 1865. Robert Worthington, F.R.A.S., Vice-President of the Section, in the Chair. Mr. Dancer, F.R.A.S., exhibited a small and cheap, but very effective induction coil, and a set of four Geissler’s tubes, in which the stratification of the electrical light was very dis- tinctly shown when a small battery of only one pair of elements was employed to produce the primary current. Mr. Brothers, F.R.A.S., exhibited a beautiful series of enlarged photographs of the moon from negatives taken during the progress of the lunar eclipse on the night of the 4th instant (see ante , page 3). Mr. Dancer stated, with reference to the eclipse, that he and his son, Mr. James Dancer, had noticed some irregu- larities on the border of the earth’s shadow which, as they maintained their forms and relative positions whilst the shadow passed over the moon’s disc, could not, he thought, be due to differences in the reflective power of different por- tions of the moon’s surface. Mr. Baxendell suggested that these irregularities might be owing to the prevalence of extended masses of clouds in certain portions of the earth’s atmosphere and their absence in others. The following table of rainfall at Eccles for 1864, was communicated to the Section by G. V. Vernon, F.R. A.S., at a meeting held April 13th, 1865 ; — 10 RAINFALL AT ECCLES, NEAR MANCHESTER, FOR 1864. By Thomas Mackeketh, F.R.A.S., M.B.M.S. Rain gauge 3 feet above the ground, 112 feet above the sea. Days of Rain Fall, 1864. Fall of Rain in inches for 1864. Average Fall of Rain for 4 years at Eccles. Average Fall of Rain for 71 years at Manchester Difference from 4 years’ fall at Eccles. Difference from 71 years’ fall at Manchester 15 1-725 2196 2-460 — -471 — -735 January. 13 3T60 1-887 2-379 +1-273 + -781 February. 15 2-375 3144 2-310 — -769 + -065 March. 12 1-722 1-977 2-038 — -255 — -316 April. 11 2-982 2-325 2-351 + -657 + -631 May. 20 2-878 3-390 2-913 — -512 — -035 June. 10 2-280 2-917 3-569 — -637 —1-289 July. 15 2462 2-959 3-592 — -497 —1-130 August. 21 4-075 5311 3-235 —1-236 + -840 September. 13 1-910 3-382 3-818 —1-472 —1-908 October. 18 3299 3104 3-473 + -195 — -174 November. 17 2006 2-815 3-260 — -809 —1-254 December. 180 30-874 35-407 35-398 —4-533 —4-524 Total. Jan. ) Feb. [ 7-260 7-227 7-149 + -033 + -111 Mar. April 3 May [ 7-582 7-692 7-302 — -no + -280 June July Aug. 3 f 8-817 11-187 10-396 —2-370 —1-579 Sept. Oct. 3 ) Nov. Dec. 9-301 10.551 —2-086 —3-336 The above table shows that the rainfall of 1864 was 4^ inches below the average fall at Manchester for 71 years, and the average fall at Eccles for four years. Both averages appear to show that the largest rainfall, in this district, takes place from July to December, which is also, to some extent, confirmed by the rainfall of last year, though there was so great a deficiency in the summer and autumn months. Ordinary Meeting, October 31st, 1865. R. Angus Smith, Ph.D., F.R.S., &c., President, in the Chair. The following communication from Sir J. F. W. Herschel, Bart., M.A., D.C.L., F.R.S., &c., Honorary Member of the Society, was read by Mr. Baxendell : — Collingwood, October 18, 1865. In the printed proceedings of the ordinary meeting of the society on the 3rd inst., I observe a notice of a paper by Mr. Greaves, “ On the Internal Heat of the Earth as a Mo- tive Power,” in which the high temperature of the carboni- ferous strata, at the depth of 4,000 feet (120° Fahr.) is spoken of as likely to oppose an insuperable obstacle to the extraction ot coal from that depth. On reading this it occurred to me that by employing condensed air, conveyed through conduct- ing pipes, as a mode of working machinery at that depth — provided the air immediately on its condensation, and before its introduction into the pit, were drained of the heat developed in the act of condensation by leading it, in pipes exposing a large external surface, through a sufficiently large supply of cold water (or in winter time of snow) — the workings below might be sufficiently reduced in temperature by the re-expan- sion of the air on its escape, when given out below in the act of working the machinery, to admit of workmen remaining there in comfort ; at the same time that ventilation would be supplied. If you think that this suggestion would be worthy the notice of the author of the paper referred to, or of those members of 'the society who may have been present at its reading, or in Proceedings — Lit. & Phil. Society. — Yol. Y. — No. 3— Session 1865-6. 12 any other way available, it is quite at your service for that purpose. P.S. — Water at 120° Fahr , or even much higher, would, I fear, afford but an inefficient moving power unless some means could be devised (without the expense of more power than the gain expected) of concentrating the heat of a large quantity of warm water into a smaller. This might perhaps be done through the intervention of air alternately rarefied and condensed. Mr. Binney, F.R.S., F.G.S., said that at the present time little is known as to the difficulties we should experience in working coal mines at a depth of 4,000 feet from the surface. The exact increase of temperature in deep mines is not by any means well ascertained. All we can say is that no great diffi- culties have been found in working at a depth of 2,100 feet. It must always be borne in mind that the deeper a mine is the greater will be the natural ventilation, that is the current caused by the air of the mine, at say a temperature of 80° Fahr., ascending the upcast shaft, while the air at the surface, of 40°, descends by the downcast shaft. No doubt a mine might be cooled by the expansion of compressed air, but it could not, so far as at present known, be done econo- mically. In most deep mines a considerable cooling of the air takes place by the expansion of the compressed gas (light carburetted hydrogen) as it escapes from the coal, where it has been long imprisoned under great pressure ; and this has not always been allowed for by observers of temperature in such places. In newly-opened mines this pent-up gas forces off large pieces from the face of the coal, and it sometimes makes a noise like water rushing over a weir. In sinking a deep shaft at Wigan some years since the compressed gas in the coal forced up about four yards of strong bind and made its way through it into the shaft. The rising of the roof of the coal as the shaft approaches it is well known to sinkers in deep and newly-opened coal fields. 13 Mr. Edward Hull, F.G.S., exhibited some etchings of caves, fissures, and isolated rocks on the coast of Cantyre, intended to illustrate three classes of phenomena belonging to the raised beach and coast, known as “ the 30-feet beach,” from the fact that its mean elevation is about 30 feet above the present tides. This raised beach has been described by several authors, from Mr. Smith, of Jordan Hill (1836), downwards, and is part of the same beach which has been traced all along the western coast of Scotland, and the vestiges of which remain in a state of remarkable freshness to the present day. Mr. T. Heelis, F.R. A.S., called attention to the proceedings of a scientific commission recently issued by his Highness the Viceroy of Egypt, who had succeeded in finding a tertiary coal basin in the valleys between Mount Olympus and the Bay of Oraniska, in the Gulf of Salonica, and also on the mainland of Asia Minor, near the Island of Samos ; and mentioned some particulars of the coal there found, such as its specific gravity, in which it slightly exceeds the ordinary coal of the coal measures, and the results of experiments upon its combustion, which give twenty per cent of ash. A paper “ On Coresolvents.” by the Honourable Chief Justice Cockle, M.A., &c., President of the Queensland Philosophical Society, was communicated by the Rev. Robert Harley, F.R.S., &c. Whatever function X may be of x equation (3) of my last paper ( Proceedings , vol. IV., pp. 37 — 40), is reducible to an equation with constant coefficients by changing the inde- pendent variable as indicated at p. 38 (ibid.'), and the order of the symbolical factors of (3) is always indifferent. Mr. Harley gives 3%(2-*)g + 3’(l-*)^+3,= l...(i) 14 as the differential resolvent of y3 - 3 y2 + 2x = 0 (ii) The sinister of this resolvent is of the form of the sinister of (3) of my last paper, and the symbolical decomposition of (i) of this paper is (i denoting as usual ± J - 1) ^3 Jx( 2~x)^- + 1'^3 Jx( 2^)-^- - 1 (iii) and the resolvent of this form of cubic, like that of the other, is soluble by change of the independent variable. The evanescence of the dexter of a resolvent does not necessarily indicate that all its algebraic coresolvents are wanting in their second term. Thus, for instance, 3.(W)g-3=*! + y = ° (iv) is the differential resolvent not only of y3 — 2>y + 2# = 0 (v) but of every algebraical equation whose roots are homoge- neous linear functions of the roots of (v), that is to say of any two of them, for any root of (v) is such a function of the other two. Let a, (3, and y be roots of an equation whereof any one root is a linear and homogeneous function of any two other roots. Then we may put y-ma + njo (vi) and, from the identities ( da d{3\ ( n\da ( dS -da \ “("£ + J - (~ + n3h = ) and (”“* + nfS)t - (m£ + nt)3 = ”(“1' we infer that and 15 and if m—n ■=. - 1 , we have dj 3 nda _ pdy _ a * dx y '}~ y dx dx dfi * dx da dx dy Xdx relations which must be satisfied by the roots of (v) or of any cubic whereof the coefficient of the second term vanishes. (Compare art. 73 of my “Notes,” &c., in the Messenger of Mathematics for November, 1864.) We have, indeed, gene- rally (“ + nfpdl + ? I) - (“ £ + nsXpa + &) = (“* ' -f ( djo n da \ adx~IJdx) a relation which of course holds when we replace a and [3 respectively by a and h, two independent particular integrals of the differential resolvent. “ Oakwal,” near Brisbane, Queensland, Australia, August 1, 1865. Mr. Baxendell drew attention to the auroral phenomena which occurred on the 19th and 26th instant, and showed sketches of the arches, &c., taken by Mr. R. P. Greg, F.G.S., at Prestwich. I)r. Joule, F.R.S., said he had observed the effect of the aurora on the former date, on his sensitive magnetic needle. The needle was violently agitated, as many as 36 changes of deflection, varying from 10" to V 40" occurring per minute. The cause of the movements seemed to be instantaneous in its action. It was remarked that when the beams prepon- derated on the west of the magnetic north the needle took an easterly direction. A paper was read entitled “ Questions regarding the Life History of the Foraminifera, suggested by Examinations of their Dead Shells,” by Thomas Alcock, M.D. 16 The author said that though shore sand did not generally yield specimens in sufficient abundance or perfection to be worth examination, yet here and there very rich shore deposits are met with, and these ought to be specially noted when observed, both because of the exhaustless supply of specimens they afford for investigation, and the peculiarity of circum- stances which must exist at these places to cause their accu- mulation. One such spot is at Dogs Bay, Roundstone, on the coast of Galway, where a great part of the shore is entirely composed of the remains of various microscopic creatures, by far the largest proportion consisting of shells of Foraminifera. Among other samples of sand from this place a very interesting one had been supplied by Mr. Parry, who had skimmed the material from the surface of pools left by the tide; it consisted entirely of fine and perfect specimens of the lighter kinds of Foraminifera, broken shells and the heavier sorts having sunk to the bottom. This naturally selected sample had furnished some very interesting results by supplying abundance of certain varieties comparatively rare in the rdugh sand, and examinations of some of these had led to the suggestions which he would now offer as to the formation of the shell in some kinds of Monothala- mous Foraminifera. He considered in the' first place that the soft body of the Foraminifer must act as a mould upon which the shell is formed, and that it must remain still and without change of shape while the process goes on ; therefore that this, so far as the foundation layer of shell is con- cerned, will be a single act, and probably one requiring no great length of time. But if the shell be moulded on the surface of the animal, it will from the first be only just large enough to hold it, and consequently whatever growth after- wards takes place must be continued outside the shell, and must constantly increase the quantity of external sarcode which has been observed coating the shells of living Fora- minifera, and which according to this view must be looked 17 upon as more than the mere result of a coalescence of the bases of the Pseudopodia. Orbulina uni versa and Globi- gerina bulloides are two forms found in great abundance in this Dogs Bay sand ; they are interesting as being the prevailing shells in deep-sea dredgings and also as always occurring together, a fact Avhich has been noticed by Pro- fessor Williamson, who has long entertained the belief that there is some very close relationship between them. The Orbulinse are found of very different sizes, the largest being as much as six times the diameter of the smallest, with every possible intermediate gradation ; and considering that the shell can only be made of the exact size of the body on which it is moulded, while that body will continue to arow, he could not avoid the conclusion that in this case at least, as often as a larger shell is required, the animal must withdraw itself entirely from the old one and cast it off. But a consequence of this view that the single-chambered Foraminifera cast their shells at intervals to form new ones is that they will occasionally be freed for certain periods from the restraint of the shell, and be in a condition to effect that spontaneous division which is so striking a feature in the Rhizopoda. There are other specimens of Orbulina found occasion- ally in the Dogs Bay sand which have a very special interest, since they appear to show most clearly that Globi- gerina is merely a younger state of this species, — a fact which was first announced by Mr. L. F. Pourtales, (Ann. and Mag. Nat. Hist. 1858), illustrated by specimens ob- tained from dredgings in the Gulf Stream. Dr. Carpenter mentions the observations but expresses doubt as to their correctness. The Dogs Bay specimens however seem to corroborate them most fully, for they show the perfect Globigerina inside the sphere of the Orbulina. 18 MICROSCOPICAL SECTION. October 16th, 1865. A. G. Latham, Esq., President of the Section, in the Chair. This being the first Meeting of the Session, the President delivered an address reviewing the past proceedings of the Section, and referring with satisfaction to the proposal to extend its objects to subjects of Natural History generally. Mr. Sidebotham read “Notes on Atlantic Soundings.” He said that in the unsuccessful attempt made to raise the Atlantic Cable after it had unfortunately parted, the ropes and grapnels brought up from the bottom small portions of ooze or mud, some of which was scraped off and preserved, as stated at the time in the newspapers. Believing that a careful examination of this deposit might prove of con- siderable interest, he wrote on the subject to Dr. Fairbairn, who, after considerable trouble, obtained for him a fine sample, mounted specimens of which he now presented for the cabinet and to each member of the Section. In appearance the deposit resembles dirty chalk, and under the microscope reminds one much of the chalk from Dover, indeed it has all the appearance of being a bed of chalk in process of formation. It is composed entirely of organisms, chiefly in fragments. In the short examination he had made, he observed several forms which give promise of interesting results, and he thought it would be desirable to frame a complete list of the species found, which would be best accomplished by two or three members taking temporary 19 possession of all the slides, and preparing a report on their united observations. The sample now distributed was ob- tained at Dr. Fairbairn’s request by Mr. Saward from Mr. Temple one of the Engineering Staff, who states that it was got in grappling for the Cable, August 11th, 1865, Lat. 51° 25' 15" N. Long. 38° 59' W. Mr. Sidebotham also read the following “ Notes on Acheron tia atropos” : — The Death’s Head Moth, which was in former times an object of such dread that the appearance of a speci- men of it was, like a comet, considered the precursor of some dreadful event, appears to be gradually becoming more common. If I remember rightly, it was Stothard the Artist who was so fortunate as to capture a specimen for his collection when a genuine British specimen was ex- ceedingly rare. Even in my recollection a guinea or two was not considered too much to pay for a fine example. This season the insect has been unusually abundant, at least a score of larvae having been found about my own neighbour- hood. It has also been found at Bowdon, Middleton, Old- ham, S trines, and other places round Manchester ; in Middle- ton about 170 have occurred. Between Lytham and Black- pool it has been remarkably common ; among those I obtained at Lytham was a very remarkable specimen, of which I made a rough drawing ; it was so unlike the usual form that many who saw it fancied it must be some other species, but the same has been noticed by Stanton as occurring now and then, and Mr. Harrison obtained another somewhat similar at Bowdon. My specimen is still in the pupa state, and I shall carefully note whether or not the moth produced varies from the usual form. Dr. Alcock read a paper entitled “ Questions regarding the Life History of the Foraminifera, suggested by Exam- inations of their Dead Shells.” This paper was afterwards read at the Ordinary Meeting of the Society, held on the 31st October. See page 15. Dr. Alcock also exhibited specimens of Eozoon Canadense, from Canada, and also from Ireland, lent by Mr. H. B. Brady. Mr. Symonds Clark, of Adelaide, South Australia, ex- hibited a series of skulls, of small Marsupial animals, beautifully prepared by him; also the skins of several species. Mr. Sidebotham recorded the discovery of Apion ononis, in the Isle of Anglesey, a species of Curculio, which he stated to be new to Britain. Ordinary Meeting, November 14th, 1865. R. Angus Smith. Ph.D., F.R.S., &c.. President, in the Chair. Mr. Charles Bailey, and Mr. Thomas Barker, M.A., Pro- fessor of Mathematics, Owens College, were elected Ordinary Members of the Society. The following extract of a letter from Thomas Ainsworth, Esq., of Cleator, near Whitehaven, Corresponding Member of the Society, accompanying a copy of his meteorological observations for October, was read by Mr. Baxendell : The great peculiarity of the season has been the very heavy dews we have had — great luxuriance of pasture nourished by dews and not by rain. I have drawn Professor Simmond’s attention to this as being a predisposing cause of the present cattle disease. Not that it really engenders the malady, but predisposes the animal to take this peculiar type of disease — my own experience from the readings of my instruments some twelve or fourteen years ago having shown that disease of the same type attacked my cattle and destroyed them, and each time when the high temperature of the day and the low temperature of night gave us such heavy dews as to render the herbage quite indigestible. Mr. Baxendell considered it very probable that cattle would be injuriously affected by feeding on herbage which had not been well washed by occasional showers of rain. Dew had little or no washing effect, and it could not remove Proceedings— Lit. & Phil. Society.— Yol. Y— No. 4— Session 1865-6. the impurities which were deposited upon the leaves of plants during long periods of dry weather. The cattle plague is said to have had its origin in Central Asia, and in this region there is very little rain, and the daily range of temperature is very great. The herbage is therefore seldom well washed, and moreover, the cattle that feed upon it are exposed to frequent and violent changes of temperature. We have no report of any cattle plague breaking out among the herds on the pampas of South America, where rain falls more abundantly and the changes of temperature are much less violent. The President said that the idea of deriving the cattle plague or any similar epidemic from the organic matter brought down by dew was at least in harmony with much that we had learnt. The dews and fogs of evening over certain lands were known to produce colds, agues, or fevers which could be avoided by rising to a certain height from the ground. There seems little doubt that the moisture in such cases is not the cause of disease, but only the means of con- veyance. These diseases were produced by breathing the impure air. We know less of the effect when the matter is condensed and conveyed into the stomach, but the effect of impure water made this use of it also suspicious. He was not aware that it could be shown that in aggravated cases another class of disease might not be produced. In Man- chester we can see the accumulation of matter taking place in the fog to such an extent that it lies like a cap over the whole town, and so increases that every sense is affected, whilst the lungs and eyes suffer severely. The matter in solution in this case is not putrefactive, although injurious, or it would probably sweep us off instantly. Probably no accumulation of putrefactive matter equal in amount ever occurred in the natural atmosphere. It illustrates, however, the mode by which the emanations of the soil are collected in the atmosphere and presented in a concentrated form for us to breathe. He had for many weeks collected dew on a grass lawn in a garden, and from it had obtained organic matters unquestionably collected from surrounding objects, as it was known on one occasion to smell of flowers. If this entered into putrefaction it would of course be unwholesome, but what kind of disturbance of health it would cause it must be for others to find. The evening air of a rainy country like this is less dangerous than that of some other climates where there is more both evaporated and condensed, and neither wind nor rain to remove it. Notwithstanding this, he believed that more than the dew was required, especially in northern climes. The President also said, that when sitting in a railway carriage with his friend, Mr. James Young, of Bathgate, that gentleman observed that the particles of dust which floated in the air seemed to shine with a metallic lustre. Dr. S. immediately collected some, and found that the larger class were in reality rolled plates of iron which seemed to have been heavily pressed and torn up from the surface. Another and smaller class were less brilliant, and when looked at with a considerable power shewed many inequalities of surface which would be interesting to study. Probably these were the particles which were not torn up but rubbed off. The dust enters the mouth and lungs, and has to be taken as one of the evils of railway travelling, although we do not know that these small particles are worse than those of sand. At any rate, it is clear that some kind of iron will wear down more readily than others, and we ought to have that which will wear down least. By observing what takes place in the carriages on a dusty day, every man may to some extent compare the iron of different railways. Those which give off the largest pieces in greatest quantities, are to that 'extent the worst, as regards health. 24 A paper was read entitled “ An Attempt to refer some Phenomena attending the Emission of Light to Mechanical Principles,” by R. B. Clifton, M.A., Professor of Natural Philosophy in Owens College. The author attempted to show, by analogical arguments, that it is possible to give some account of certain phenomena attending the Emission of Light, by assuming principles closely resembling, if not identical with, those adopted by Professor Clausius in his well known paper on “ The Nature of the Motion which we call Heat.”* Matter is assumed in all cases to have its atoms grouped together into molecules, an assumption which seems necessary when the different allotropic states of certain substances are considered. These molecules are assumed to be in motion, and also the atoms to be vibrating in the molecules ; for, whatever may be the laws of the forces which bind together the atoms in the molecules, it is impossible to imagine the molecules to be in motion, and to be subject to mutual actions, without causing motion of the component atoms. In solids and liquids the molecules are supposed to remain continually within the spheres of action of neighbouring molecules, so that the internal motion in a molecule is never due to the undisturbed action of the interatomic forces — the only difference between solids and liquids being that in the former the same molecules are constantly neighbours, while in the latter a molecule may completely change its place in the liquid, and also that in liquids a molecule may perform complete rotations round axes through its centre of gravity, while in solids this is not generally possible. In a perfect gas a molecule is supposed to be under the action of other molecules, only for a portion of time in- definitely small with respect to the whole time of motion, and its centre of gravity describes a polygonal path, only * Phil. Mag., vol. sir., for 1857. 25 changing its direction of motion upon the near approach of the molecule to another molecule, or to a containing vessel, which may be considered as equivalent to an impact. In an imperfect gas a molecule is supposed to be under the action of other molecules during a finite portion of the whole time of motion, this portion increasing as the gas approaches its state of saturation. Between the molecules of a body, and the atoms of a molecule, the luminiferous ether is supposed to exist. The vibrations in the ether which constitute radiant heat and light, are considered due to the vibrations of the atoms in the molecule, and not to the motion of the molecule as a whole ; the latter bearing some such relation to the ether, as a bell or a stretched string does to the air, the internal vibrations only in the two cases causing the vibrations in the surrounding media, which give rise respectively to light and sound. It appears obvious that as the motion of a molecule of a body as a whole increases, that is, as the temperature rises, the internal motion in the molecule also increases, considering that the action of one molecule upon another must be due to the mutual action of atoms, or to the interatomic forces, it seems probable that the internal vis viva in a molecule, to which the light is due, is proportional to the vis viva of the molecule as a whole, to which heat is to be referred. Thus, as the temperature of a body rises, the internal vis viva in the molecules increases, and the vis viva communicated to the ether also increases ; hence the intensity of the vibration in the ether increases, and at the same time the period of vibration diminishes, or waves of shorter length are con- tinually produced with increasing intensity. Hence as the temperature of a body rises radiant heat is given off, the intensity corresponding to a given wave length - constantly increasing, at last then vibrations in the ether, with wave lengths corresponding to the extreme red of the 26 spectrum, will be caused with sufficient intensity to be visible, and thus the body will begin at first to glow with red light ; as the temperature still rises, and vibrations of shorter and shorter wave lengths become of visible intensity, the light emitted will gradually change from red to white. From Draper’s Law, that all bodies become incandescent simultaneously, as well as from other considerations, it seems probable that in all bodies the internal vis viva in the mole- cules bears the same ratio to the vis viva of the molecule as a whole. In solid and liquid bodies, the molecules being constantly under their mutual actions, and these actions being subject to constant change from the varying relative positions of the molecules, the atoms cannot assume any definite periods of vibration, but are constantly changing the time of vibration ; hence the vibrations in the ether will be constantly, and with extreme rapidity, changing their periods. This change having apparently no limit, and the effect upon the eye con- tinuing for a finite time, light of all wave lengths will appear to be given off simultaneously by such bodies when the tem- perature is sufficiently high ; in other words, incandescent solids and liquids will appear to give off Avhite light, which when analysed by a prism will yield a continuous spectrum. In the case of an incandescent Gas or Vapour sufficiently removed from a state of saturation to be considered per- fect, the atoms will be left to vibrate under the action of the interatomic forces only, and will thus assume periods of vibration all included in a certain set ; these vibra- tions Avill consequently cause vibrations in the ether corre- sponding only to certain definite wave lengths. Hence the spectra of such incandescent vapours will be broken, and consist only of a series of fine lines. With imperfect gases, or vapours not far removed from their points of saturation, the intermediate phenomenon of spectra broken, but consisting of bands, is to be expected : 27 when however the temperature of such vapours is sufficiently increased, a change from spectra consisting of bands to spec- tra consisting of fine lines is to be looked for. This change has been observed in many cases. When a solid body is incandescent, the light emitted so as nearly to graze the surface may be considered due mainly to the surface molecules, but these being free on the side of the surface, but affected by other molecules on all other sides, the internal vibrations in these surface molecules will have a bias in a direction perpendicular to the surface. Thus the vibrations caused in the ether, Avhich are propagated nearly grazing the surface, will preponderate in a direction perpendicular to the surface, or considering the vibrations in plane polarised light to be perpendicular to the plane of polarisation, the light emitted by such a body, so as to pass close to its surface, will be partially plane polarised, the plane of polarisation being parallel to the tangent plane to the surface of the body at the point of emission. In the case of an incandescent gas, the surface molecules are coir tin ually changed, and as a molecule may arrive at the surface in any position and is equally free on all sides, all trace of polarisation in this light will be destroyed. The fact that incandescent metallic plates do emit partially plane polarised light in directions nearly grazing the surface, the plane of polarisation being parallel to the surface, and that incandescent gases emit unpolarised light, has been observed by Arago. As the molecules at or near the surface of solids or liquids can cause vibrations in the ether, giving rise to emitted light, it is to be expected that, in some cases at least, it will be possible for light, if of sufficient intensity, when incident upon a body, to cause vibrations in the atoms constituting the molecules near the surface, but considering the difference of mass of the atoms of the body and of those of the ether, that the atoms of the body will vibrate slower than those of 28 the ether, the actual times of vibration depending however upon the molecular forces in the body. As these atomic vibrations will again affect the ether, such bodies will or may become luminous, the wave lengths of the emitted light being however longer than those of the incident light which causes the disturbance in the body. This emitted light will necessarily last some time after the incident light is removed, for the vibrations in the body will not cease as soon as the cause of disturbance is removed, but in general it is to be expected that this emitted light will speedily disappear, though cases may occur in which it will continue for a considerable time. These probable deductions from the assumed principles coincide exactly with the phenomena of Fluorescence and Phosphorescence (not including in this term cases in which light is emitted by bodies undergoing slow combustion), all Fluorescent bodies being Phosphorescent for times of different, though in all cases at present observed, of very short duration. PHYSICAL AND MATHEMATICAL SECTION. November 9th, 1865. E. W. Binney, F.R.S., F.G.S., President of the Section, in the Chair. Mr. Baxendele, F.R.A.S., read the following “ Note on the Variable Star S Delphini.” Since the discovery of this variable in October, 1863, it has gone through two complete periods of change, and my observations have enabled me to fix with tolerable exactness the dates of three maxima, and to determine the form of the light-curve for that portion of the period during which the 29 star is visible with telescopes of moderate power. Comparing the light-curves for 1864 and 1865 with the curve laid down from the observations made in 1863 after the discovery of the variable, I conclude that a maximum occurred about the 14th of October, 1863, the magnitude being*8'5. The next maximum occurred on the 12th of September, 1864 — mag- nitude, 8'3 ; and the third on the 9th of August, 1865 — magnitude, 8*9. The interval between the first and second maxima is 334 days, and that between the second and third, 331 days. The mean period is therefore about 332 days. In the Astronomische Nachrichten, No. 1523, Dr. Schonfeld states that this star was observed on the 8th of September, 1855, in zone 7^4 of the Bonn “ Durchmusterung,” and estimated to be of the ninth magnitude, but was invisible to Professor Argelander with the telescope of the Bonn meridian circle on the 9 th, and with the heliometer on the 20th of November following, and was therefore not inserted in the “ Bonner Sternverzeichniss,” its existence evidently being considered doubtful. Guided by the course of the star’s light-curve, I conclude from the Bonn observations that a maximum occurred about the 12th of August, 1855. The interval between this date and that of the last maximum, August 9th, 1865, is 3,650 days, during which time the star passed through eleven complete periods of change. We find ' therefore that the value of the mean period is 33 T8 days, a result agreeing very closely with that derived from my own observations alone. An inspection of the diagrams which accompany this com- munication will show that S Delphini increases in bright- ness much more rapidly than it diminishes, and that the course of its light-curve is more irregular after than before a maximum. During the last apparition it rose from the thirteenth magnitude to a maximum in 48 days, but was 89 days in descending again to the same magnitude. When at minimum it is below the 13^ magnitude, and it remains 30 invisible with telescopes of ordinary power for more than the half of its entire period. Mr. G. Knott, F.R.A.S., of the Woodcroft Observatory, Cuckfield, Sussex, has kindly favoured me with a copy of his observations of S Delphini, made during the present year, and of the light-curve laid down from them. He has obtained for the date of maximum August 1 1, 1865 — magnitude, 8'8. Considering the nature of the observations, and the form of the light-curve at its maximum, this result agrees very fairly with that derived from my own observations. It will how- ever be seen that there is a slight difference in our modes of drawing a curve through the points laid down ; Mr. Knott evidently regarding apparent irregularities as being principally owing to errors of observation, Avhile, on the other hand, I have regarded them as being mainly due to actual changes in the brightness of the star. Treating his observations pre- cisely as I have treated my own, I do in fact, obtain the same date of maximum, August 9, 1865. The colour of S Delphini is decidedly “ reddish,” and my observations seem to indicate that this colour becomes sensibly more intense as the star approaches its minimum. The difference of O’ 1 between my own and Mr. Knott’s estimations of magnitude at the last maximum is doubtless due to the colour of the star, and to the fact that while my observations have been made with a telescope of five inches aperture, Mr. Knott’s have been made with one having an aperture of seven and one-third inches. Eeeatum.— l’ugo 20, last paragraph, for apion ononis, read apion ononidis. 31 Ordinary Meeting, November 28th, 1865. R. Angus Smith, Ph.D., F.R.S., See., President, in the Chair. Mr. Francis Hampson, Solicitor, was elected an Ordi- nary Member of the Society. Mr. Dancer, F.R.A.S., said that in a paper “ On the Illumination of Opaque Objects under the high powers of the Microscope,” read before the Microscopical Section of this Society, November 20th, he had described a method of employ- ing the oblique body of the binocular microscope with Wenham’s prism, for illumination of opaque objects, and he had also exhibited an instrument fitted up for this purpose, giving the members present a practical demonstration of the advantages which this mode of illumination afforded under certain circumstances. He wished now to describe another method of illuminating opaque objects, and as it is equally applicable to monocular and binocular microscopes, it appears worthy of some consideration. In the method of Mr H. L. Smith, of Kenyon College, (which was briefly described in the paper before mentioned), and also in the use of the Wenham’s prism there is a con- siderable loss of angular aperture, (which is a very important consideration) : it occurred to the author that by modifying Mr. Smith's contrivance this loss might be diminished in some degree ; this has been attempted in the following manner. Proceedings— Lit. & Phil. Society,— Vol. V.— No. 5— Session 1865-6, 32 Instead of placing the mirror immediately over the opening at the hack of the object glass, a small speculum £ of an inch in diameter is introduced into the front of the body of the microscope, 24 inches above the top of the objective. A lateral opening is made in the body at right angles to the speculum, for the admission of light to be reflected down through the objective to the object below. The interposition of the small speculum does not produce any disagreeable effect in the field of view, and in the exami- nation of objects it is easy to use that portion of the field which is between the centre and the edge. With proper manipulation very good definition can be obtained by this method, when the speculum is of the proper curvature. This contrivance can always remain attached to the microscope without inter- fering with the general appearance of the instrument, and when the use of the speculum is not required, it can be with- drawn or turned aside out of the field of view, and the aper- ture at the side of the body may be closed by a small shutter. It is obvious that the use of the binocular body is not inter- fered with by this arrangement. A binocular and a monocular microscope with this arrange- ment were exhibited to the members at the close of the meeting. Mr. Hardy (on behalf of Edward Ross, Esq.) exhibited a large cetacean vertebra which had been found in the valley of the Don, about two miles from Tinsley and four from Rotherham, in Yorkshire, on a line of railway now in course of construction. The bone was met with in excavating, at a depth of 14 feet below the surface of the ground, in a bed of gravel overlaid by the alluvium of the valley. In answer to questions put by Messrs. Binney and Hull, Mr. Hardy described the bone as one of the lumbar vertebrae of a species of whale, probably identical in genus witli the baleena of the present seas. The bone measured on its largest diameter a little over ten inches, in thickness seven inches, and in cir- cumference about three feet. It presented every appearance of having lain in the earth for a very considerable length of time ; but as it only reached Manchester on the day previous, the geological character of the gravel in which it was found had not been ascertained. Dr. Roberts drew attention to the injurious effects pro- duced by burning Pharaoh’s serpents in close rooms, and gave the particulars of a case which had lately come under his notice. Dr. Roscoe stated that in his opinion persons could not be too careful respecting the inhaling of even small quantities of mercury vapour, and he alluded in support of this opinion to the fact that two German gentlemen who were engaged in a London laboratory, in the preparation, for a scientific purpose, of volatile organic mercury compounds, had recently been poisoned by the accidental absorption through the lungs or skin of very small quantities of the vapours of these sub- stances. The symptoms characteristic of this form of mercu- rial poisoning are of the most painful and distressing kind, the first patient dying in a state of mania shortly after his admission into the hospital, and the second, on whom the effect became first perceptible three months after he had ceased to work with the substance, now lying in a hopeless state of idiocy. A paper was read “ On the Amount of Carbonic Acid con- tained in the Air above the Irish Sea,” by Mr. T. E. Thorpe, Assistant in the Private Laboratory, Owens College, com- municated by Professor H. E. Roscoe, F.R.S. The determination of the amount of carbonic acid contained in the atmosphere over the land has been made the subject of investigation by many experimenters, and from the results ' obtained by Theodore de Saussure, Brunner, Boussingault, Angus Smith, and others, we are acquainted with the exact 34 proportion of this gas contained in the atmosphere under varying circumstances of situation and weather. But hitherto, the influence which, a-priori, must necessarily be exercised by large bodies of water on the proportion of carbonic acid in the atmosphere has scarcely been sufficiently studied. The fact that a considerable influence is exercised has certainly been noticed, but beyond the incomplete results of one or two observers, we have no numerical data from which to judge of the extent of this influence, and we there- fore know but little of the changes in the comparative amount of the atmospheric carbonic acid as effected by the waters of the ocean. Dr. Roscoe therefore suggested that I should undertake some experiments on this subject, and kindly placed the necessary time and apparatus at iny disposal. I may here be allowed to express my thanks for this kindness, and for the advice I have received from him during the prosecution of these experiments. It appeared from the observations of Vogel on the air of the Baltic and of the Channel that the sea abstracts to a very considerable extent the carbonic acid from the atmosphere ; and this conclusion was apparently confirmed by the experi- ments of Emmet on the air over the Atlantic and at Bermuda, and by the determinations of Watson at Bolton, made on air blowing from the seaward. These experiments were however, for the most part, merely qualitative, and the circumstances under which they were made, together with the inaccurate nature of the methods employed, render such a conclusion premature. In fact, the experiments of Lewy and Morren on the nature of the gases which sea water holds in solution at different periods of the day and during various seasons of the year would appear to show that the sea may possibly act in quite the opposite direction, and cause a sensible increase in the comparative amount of atmospheric carbonic acid. 35 The air contained in sea water consists of variable quanti- ties of free carbonic acid, oxygen, and nitrogen, and Morren and Lewy have shown that the changes in the relative pro- portion of these gases depend: — (1) upon alteration of tem- perature affecting the relative amounts of the dissolved gases in accordance with the laws of gaseous absorption ; and (2) upon the variations in intensity of direct and diffused solar light, producing a corresponding effect upon the vitality of sea plants and animals, and hence altering the composition of the dissolved gases. Some further experiments by Lewy, on the composition of the atmosphere above the Atlantic ocean in the tropics, tend to confirm the above supposition of the possible increase in carbonic acid in the atmosphere above the sea. In fact, if it is possible that the composition of the air above the sea in our latitudes can be sensibly altered by this phenomenon of the variation in the nature of the gases in solution in sea water, as Lewy and Morren assert, we might expect that the atmosphere above the tropical oceans would manifest to a much larger extent variations in the relative amounts of carbonic acid and oxygen, since infusoria exist, as is well known, in enormous quantities in these oceans, and the composition of the air in their waters must necessarily undergo rapid variation, and a considerable evolution of the dissolved gases must consequently occur. At the instance of the French Academy Lewy collected air at different times during a voyage from Havre to Santa Marta, and on subsequent analysis not only did it appear that the mean quantity of carbonic acid was sensibly greater in the air of the Atlantic ocean in the tropics than in the air of the land, but also that the air of the day was appreciably richer in carbonic acid and oxygen than air collected in the night. On comparing the means of each series we have, in 10,000 volumes of air, for the 36 Day (mean of 7 expts.) Night (mean of 4 expts.) Carbonic acid 5”299 3"459 Oxygen 2105-801 2097-412 and this variation appeared to increase in proportion as the middle of the ocean was approached. This remarkable phenomenon, of the variation in composi- tion of the air above the tropical oceans, may doubtless be accounted for, without any reference to the direct action of infusoria, by the heating effect of the sun on the sea water and the consequent disengagement during the day of gas pro- portionately rich in carbonic acid and oxygen. During the night, on the other hand, as this source of action is removed, the disengagement may be assumed not to occur ; and, follow- ing Lewy, one may perceive that this difference would be- come more appreciable and easier to trace in air at great distances from any continent than in air collected nearer the coasts, and consequently, liable to be mixed with the air of the land. Although the precision of these results is certainly remark- able, they still require confirmation. The air was collected in glass tubes of about 100 cbc., and analysed eighteen or twenty months after in the eudiometric apparatus of Reg- nault and Reiset. The fact pointed out by Regnault that air which has remained for any great length of time in glass tubes invariably exhibits notable diminutions in the amount of carbonic acid, since the glass absorbs a portion of this gas; and the difficulty generally experienced in accurately noting contractions so minute as the absorption of the carbonic acid from a small volume of atmospheric air, are circumstances which may possibly influence the reliability of the results. The kind permission of the Honorable Board of Trinity House has enabled me during the vacation of last summer to make some additional experiments in this direction on board the “ Bahama Bank ” Light-vessel, situated in the Irish sea, latitude 54° 21' and longitude 4° IT, seven miles W.N.W. of Ramsey, Isle of Man, and consequently nearly equidistant from the nearest shores of England, Scotland, and Ireland. The ship is placed to mark the proximity of a dangerous bank, by which, for the greater part of the day, a strong current, setting in from the southward, flows through the North Chan- nel and thence into the Atlantic. These experiments were made in the early part of August, at the same periods of the twenty-four hours, namely about 4 a.m. and 4 p.m , or nearly the times of minimum and maximum temperature. Pettenkofer’s method of analysis was adopted, with the improvements in the practical details suggested by Angus Smith. This method is in principle similar to the one adopted by Watson and Emmet, but admits of far more deli- cacy and precision in practice. Baryta is substituted for lime water, and oxalic for sulphuric acid. The solution of oxalic acid for these experiments was made so that one cubic centimetre of it corresponded to one milligramme of carbonic acid ; it thus contained 2’864 grms. of pure crystallised oxalic acid per litre. Twenty-five cubic centimetres of the baryta solution were originally made to correspond to about twenty- eight of oxalic acid, but of course the exact strength of the baryta water was ascertained previous to each experiment. The bottles were generally filled with the air by means of the bellows, but sometimes when the wind was strong it sufficed to hold them up for a minute or two in such a manner that the air could circulate freely within. The baryta water remained in contact with the enclosed air for three quarters of an hour to one hour, during which time the bottles were fre- quently agitated. Although even this is longer perhaps than is actually required for the complete absorption of the car- bonic acid, still, for the sake of conclusiveness, in experiment 4 the bottles were allowed to stand for three hours, and in .experiment 13 for six hours, before the solutions were tested. The capacities of the two bottles which served for all the ex- 38 periments were 4815 cbc. and 4960 cbc. The burette was Mohr’s modification, for which a table of calibration had been constructed by weighing and interpolating in the ordi- nary way. The fact that the various meteorological changes influence to such a remarkable extent the nature and amount of the gases dissolved in sea-water renders it necessary, in any investiga- tion on the constitution of the atmosphere over the sea, to take particular account of these changes. Accordingly the temperature, pressure, and degree of humidity of the air ; direction and force (estimated — Beaufort’s system) of wind ; amount (estimated — overcast=10) and nature of clouds, and general appearance of the day, together with the temperature of the sea water and amount of sea disturbance (1 to 9), were noted at the time of each experiment. The following table shows the results of these observations, together with the amount, in volumes, of the carbonic acid in 10,000 volumes of air. All the experiments which were made are here given. The hours of observation, as before stated, were 4 a.m. and 4 p.m. TABLE OF RESULTS. 39 24 a g o Ph c? rd 0 c3 © a cd J? ■* d d M on t _g __, <35 »■* d a . p. rt 03 rd w .9 ^ rt *3 © S t Is S rf-l* ® 1 S f.g5 g h c3 O -p 0 ^ -P 3 (> !> b a M .3 ’c o H W •d oq q> o CO 305 3-21 05 X 05 © u 3 O ■$ T fc-g 11 ^ g -s H O cj TO ! — *' 43 § o O u <25 o PI 3 O £h Jj ’o 3 3 a g p o M Jh .§ 6 © 6 | © % P5 i-H £ £ rO £ P5 PH. rd P £ £ £ £ ft rO CQ R ft 02 oq GQ izi izi CZ2 02 02 CQ iZ! £ & S1! © EH m O oopptpppopipipoo ;bibibw>ibtt5cbw3i}5T} 05 H w CD O0 CD x> bo X bo ib ib bo bo fi rH rH rH rH rH r-H rH r-H rH rH rH rH rH l a lO O oq lO oq O x> X ID oo rH © a bq bq bo 6 rH bo CD 05 6 oq bo X CD X uo uo X X ID ID ID ID ID x> i>» J> t> l> q> x> i> 43 -d . 1*, m a © g °P R }z5 R »z; R & R '4 R R R & X i— ' d= X. r- X X rt +3 4-« 3 00 id CD X X ■05 O r-3 CD X rH rH rH rH 6 rH cq cc ID CD X 05 O r-H oq CD & r— < rH rH rH Day Mean of 14 Determinations 3086 ’ Night „ 12 „ 3 085 40 In comparing these results with the following determinations of the carbonic acid contained in land air, it is seen that the air of the Irish Sea contains a much smaller proportion of carbonic acid than the air of the neighbouring land. The most extensive observations on the land air have given as means : — Observer. Locality. No. of Expts. Vols. in 10,000 of , Th. de Saussure, Chambeisy, 104 4-15 Boussingault, Paris, 142 3-97 Verver, Groningen, 90 4-20 Roscoe, 1st series, London & Manchester, 108 3-97 „ 2nd series, Manchester, 53 3-92 Smith, ditto. 200 4-03 General mean of land air 4-04 Mean of 26 expts. on sea air 3-086 It would also appear that no difference is discernible in the amount of carbonic acid in the air of day and night over the Irish Sea. On the other hand, from Saussure’s observations a decided difference may be traced between day and night air on the land — a conclusion subsequently confirmed by several experimenters. In noting the above mean 3 ’08, and the apparent identity in the amount of carbonic acid in the air of day and night over the sea, it should be borne in mind that July and August are, in general, the hottest periods of the year, (these months were unusually hot this year, 1865) and that, consequently, all the influences may be supposed at work which would tend to increase the relative amount of carbonic acid, and render- appreciable any difference in the air of night and day. The conclusions therefore to be drawn from these experi- ments are : — 1 . That the influence of the sea in our latitudes in abstract- ing the carbonic acid from the atmosphere is not so great as the old experiments of Vogel and others would lead us to suppose. 41 2. That the sea in our latitudes does not act in increasing the amount of carbonic acid in the air above the ocean, as found by Lewy over the Atlantic near the equator. 3. That the differences observed in the air of night and day by Lewy on the Atlantic, are not perceptible in the air above the Irish Sea. 4. That in the month of August 1865, the mean quantity of carbonic acid in the atmosphere of the Irish Sea was 3*08 in 10,000 volumes of air. In conclusion, I beg to acknowledge the kind attention which I received from Captain Temple, and from his crew during my stay on board his ship. 42 MICROSCOPICAL SECTION. November 20th, 1865. A. G. Latham, Esq., President of the Section, in the Chair. Mr. Parry read a paper on “ Collecting Foraminifera on the west coast of Ireland.” He said that in June last he visited the coast of Connemara, for the purpose of collecting Foraminifera, more especially at Dogs Bay ; he was accom- panied by Mr. Burns, of Doohulla Lodge, who gave him much assistance. After he had procured a considerable quantity of the shell-sand in the usual way, he noticed some white floating material on the surface of the advancing tide ; he collected a quantity of it by means of a muslin net, and on examination found it nearly all composed of perfect dead shells of Foraminifera. On a second visit to the bay Mr. Burns discovered a pool near high water mark, covered with the floating shells, and of these Mr. Parry collected a large quantity, portions of which he had since distributed to mem- bers of the Section. He observed that the underside of the rocks forming the pool were covered with foraminifera, and he therefore concluded that these minute creatures live there, and from what he saw he was led to believe that Dogs Bay is a breeding ground for them, and that they may also be found living in “ Burns’ Pool.” Mr. Dancer, F.R.A.S., read a paper “ On the Illumination of Opaque Objects under the high powders of the Microscope.” 43 The Author’s attention was drawn to a paper on this subject, which appeared in the Scientific American, and was copied into the Mechanics’ Magazine of October 20th, 1865. Mr. H. L. Smith of Kenyon College, had contrived a plan for the illumination of opaque objects, by placing a small mirror in a'rectangular box, which could be attached to any ordinary microscope, this mirror was made adjustable imme- diately over the opening of the back of the objective, a light was placed at the side of the box and reflected down through the objective on to the object. In this manner the object could be illuminated when the high powers were used. Mr. Hurst suggested that a discussion on this subject would be of interest to the members of the Microscopical Section. The Author not having time to make one of Mr. Smith’s apparatus, thought it possible to arrive at similar results by the employment of the binocular microscope, an instrument which is now more common than a monocular instrument. The trial quite answered his expectations. The simplest method and one which gave good results, is to remove the eye piece from the oblique body and fix a reflector on the top of the body in such a manner as to throw the rays of light down to the Wenham’s prism, and thence through the object glass on to the object. If a plane mirror is employed, a lens of suitable focal length should be placed in the body in order to get the field of view entirely illuminated. A concave mirror or lenticular prism can also be used for the same purpose, providing the focal length is adapted to the length of the body and object glasses. Various modifications can be adapted so as to vary the character of the illumination to suit the particular object to be viewed. In some cases the Wenham’s prism may be withdrawn a little, to produce the proper effect. 44 Uncovered objects only can be seen to advantage, owing to the light reflected from the surface of the covering* glass. The surface on which the objects are mounted should reflect as little as possible, and be a marked contrast in colour to the object. 4 45 Ordinary Meeting, December 12th, 1865. R. Angus Smith, Ph.D., F.R.S., &c.. President, in the Chair. Mr. J. Bottomley said that a recent paper upon the employment of the internal heat of the earth led him to con- sider what might he the condition of the atmosphere when coal, lignite, anthracite, and all other forms of vegetable fuel should be so exhausted that the human race would be com- pelled to resort to this source of heat. The numbers obtained led him to the conclusion that the exhaustion of the coal fields implied more than the depriving of the human race of a ready source of warmth, namely, the alteration Of the atmosphere to an extent that would ultimately prove fatal. As the latter assumption seemed to him to be repugnant to reason, he would infer that long before the exhaustion of the coal fields, the carbonic acid in the atmosphere beyond the limits of safety to life, would have been decomposed by vegetation ; moreover, as plants decomposed water, there would always be some combustible compound of carbon and hydrogen ; in other words, there will and must be abundance of fuel in the world in all ages, if not of so dense a character as anthracite and coal, yet of some nature intermediate between those fuels and vegetable tissue, the origin of all varieties. The effect of vegetation in maintaining the purity of the atmosphere has long been known. The assumption that this agency is sufficient to furnish an abundant and per- petual supply of fuel to mankind involves no new principle, but it tends to establish a new inference upon principles already Proceedings — Lit. & Phil. Society — Yol. Y. — No. 6. — Session 1865-66. 46 acknowledged. Liebig states, in his “ Chemistry in its Application to Agriculture and Physiology,” (3rd edition), that the quantity of carbon existing in the atmosphere amounts to more than the weight of all the plants and of all the strata of mineral and brown coal existing on the earth. This would seem to favour the notion that the mineral and brown coal available for combustion would not affect the atmosphere to any serious extent if consumed. He has assumed more carbonic gas to exist in the atmosphere (toW by weight) than many authorities would allow. Moreover, since the book was written enormous deposits of fuel have been discovered. In another passage Baron Liebig seems to favour an opposite view, for he states — “ In former ages, therefore, the atmo- sphere must have contained less oxygen, but a much larger proportion of carbonic acid, than it does at the present time, a circumstance which accounts for the richness and luxuriance of the earlier vegetation.” Dumas and Boussingault say, in their book on the chemical and physiological balance of organic nature, “ If we suppose, then, that the whole of the carbon was diffused through the atmosphere in the shape of carbonic acid prior to the creation of organised beings we shall see that the atmosphere, instead of containing less than the one-thousand part of its bulk of carbonic acid as at present, must have contained a quantity which it is not easy to estimate, but which was perhaps in the proportion of 3, 4, 5, 6, and even 8 per cent.” Mr. Hull, in his “ Coal Fields of Great Britain,” taking 4,000 feet as the depth capable of being worked, estimates the supply from the English and Welsh coal fields at 60,000,000 tons for 1,000 years. In the same book it is stated that the American coal fields are 72 times greater than the English and Welsh. In the reports furnished to the Admiralty some years back, by Dr. L. Playfair and Sir H. De la Beche, there is given a table showing the average composition of Welsh, Newcastle, 47 Lancashire, Scotch, and Derbyshire coal. The mean of these numbers is as follows: — Carbon, 80‘40 ; oxygen, 7*16 ; hydro- gen, 5*19. Subtracting from the amount of hydrogen the quantity corresponding to 7T6 of oxygen there remain as combustible material in one part of coal — carbon, 08040 ; hydrogen, 0-0421. For combustion it requires 2-4828 parts of oxygen, and produces 2*9480 parts of carbonic acid. Sir J. Herschel, in his “ Meteorology,” takes as the approximate weight of the atmosphere 11 x 1018 pounds. If we take as the amount of oxygen in the atmosphere 23 04 per cent by weight, and as the amount of carbonic acid '05 per cent by weight, the following numbers are obtained (assuming 1X10U pounds as the unit of measurement): — Weight of atmosphere 110000; oxygen contained 25344, carbonic acid contained 55; weight of coal, 98T12; oxygen required for combustion, 243-59 ; carbonic acid from combustion of coal, 289*23 ; total carbonic acid, 344-23 ; ratio of oxygen to carbonic acid at present, 460'8 to 1 ; ratio after combustion of assumed quantity of fuel, 72'9 to 1 . The last ratio can of course only be regarded as an approxi- mation, but when we take into account all the available fuel in the world — wood, peat, lignite, coal, anthracite, also the quantity of carbonic acid evolved from volcanic districts — and remembering the opinion of a member of this society, that we know little about the difficulties likely to be encountered in mining operations at a depth of 4,000 feet — there seems little reason to doubt that the ratio of the oxygen to carbonic acid would be reduced considerably below the number above stated, and that the quantity of carbonic acid in the atmo- sphere would reach a point much beyond that at which it becomes deleterious to human life. It seems then more reasonable to take the alternative and maintain that the carbonic acid will be de-oxidized, and that there will always be an abundance of fuel. 48 A paper was read entitled “ Notes on the Origin of several Mechanical Inventions, and their subsequent application to different purposes.” Part II. By J. C. Dyer, Y.P. The Employment of Steel for Transferring Engravings. At the beginning of this century, upon the death of Washington, medals to commemorate that event being called for, Mr. Jacob Perkins (then a silversmith at Newbury Port, near Boston) undertook to supply them, and, as they were required in large numbers speedily, he devised a summary process of transferring the engraved design, from prepared steel dies or stamps, by which he obtained several from one original die, and thus a vast number of medals were rapidly produced. Shortly after Mr. Perkins applied the same principle of transferring engravings for bank notes, on which very elaborate designs were printed to prevent or render their being forged very difficult by the hand of the engraver. To effect this he procured cast steel plates, and decarbonated their surfaces to the depth of about one- sixteenth of an inch, which were thus converted into very soft and pure iron; the letters and designs for the notes being then engraved upon them they were case hardened and tempered for use, but in lieu of printing from these plates they were used as dies for making others to print with. His next process was to prepare a cast steel cylinder, which in like manner was decarbonated at the surface, and then under a strong traversing pressure it was rolled over the letters and figures engraved on the hardened plate, and these engravings were taken up in relief on the surface of the soft cylinder. This cylinder being then hardened and tempered, was used to transfer, by means of the same traversing pressure, the entire work upon its surface, to any number of copper or soft steel plates for printing with. The adoption of this plan by several banks, for having very elaborate engravings on their notes, turned the counterfeiters 49 upon other banks whose notes would be so much more readily forged, which led to an extended demand by the other banks. In the year 1809 Mr. Perkins communicated* to me the details of his process of transferring engravings, with a view to having the invention patented in England for our joint account. From the success of his plan in America its adoption here was anticipated, and still further development of it looked for from the higher state of the graphic arts in London. With this view I took out patents, and minutely specified “ the method of carrying the invention into effect.” A very beautiful design was then obtained from the classic pencil of the late Sir R. Smirk, R.A., which was engraved by Reimback, on prepared steel, for printing bank notes. But I could not succeed at that time to induce the Bank of England or any other bank to adopt the plan, nor could the booksellers then be made to perceive the importance of the transferring system for illustrating books, for which it has since been so extensively used. The time had not arrived when public attention could be drawn to the bank note forgeries as a national evil and the disgrace of hanging men for a feat so readily performed as that of forging the one pound notes then in general circulation. If any excuse can be offered for this apathy, it may be said that the passions and interests connected with the war, together with those yet more embarrassing that arose from the transitions from war to peace, caused such disturbances in the circulating medium and in the general interests of commerce and industry, that it became very difficult to awaken public attention to the great scandal of relying solely upon the gallows for preventing forgeries. It has been above shown that Perkins’ invention was not for engraving on steel plates for printing, nor for engraving .upon steel at all, but rather for engraving on soft iron of homogeneous structure. It was found that all wrought iron 50 is more or less fibrous and unfit to receive delicate engra- vings, and that by decarbonating the surface of cast steel a pure iron surface was obtained, and this being engraved on, was case hardened and used for transferring and printing as before stated. This should be kept in view, because many persons have supposed that the invention of Perkins was merely the substitution of steel in the place of copper for engraving upon ; such a substitution of the one metal for the other would not be an invention in any fair sense of the word. But his method of obtaining soft iron surfaces to receive the work, converting these surfaces back into steel, and then transferring the engravings to other plates for printing, comprised together a series of novel processes which confer lasting honour upon the inventor. After the transition period, having better hopes of success, I recommended Mr. Perkins to come over himself to explain his system and aid the artists here in putting it into opera- tion. Accordingly in the year 1820 Mr. Perkins came to England, and being over sanguine, brought a large staff of able artists, mechanics, &c., but he could not bring any money to aid in establishing his intended works in London. He had assumed that capital could always be obtained in England for conducting any safe and profitable schemes. Now the matter of proving his to be such was not easy to establish with the monied class ; so to me alone, not of that class, he had to look for the entire expenses of his mission, and this I could only bear for a few months. After some time the late Mr. Charles Heath, the eminent engraver, was induced to join Mr. Perkins and become a partner in the engraving works which were then commenced in Fleet-street, and are still continued by their successors. Besides the printing on paper, Mr. Perkins’ system of transferring has been since very extensively employed for calico printing, and in later years we have also seen his pro- cess employed to a vast extent in many other departments of 51 the graphic art, such as post office and receipt stamps, and other prints that are required in greater numbers than could be produced by other than steel plates or stamps. His system of engraving on steel has at length become a great artistic power, the wide-spread increase of which has given employment to labour and capital to a vast extent in the several branches of art before stated, and from which I believe many large fortunes have been made, hut little other than “ toil and trouble” ever accrued to the inventor of them. When any important discoveries in physical science are made they never die, whatever may chance to their authors. The new facts brought before the public go forth like seeds cast upon a fertile soil, yielding the fruits of continual pro- gress among the families of men who seek improvement. It seems only just then that each generation should transmit to the next some record of the names of those contemporaries to whose genius and talents all nations are indebted for such discoveries. Wherefore, in addition to the four distinguished inventors brought to the notice of this Society in my former papers, I have "in the present one aimed to place that of Jacob Perkins as a worthy contributor to the advance of those branches of art to which his inventions have been applied. Appendix I. On the Compression of Water. In tracing the progress of steel engraving I had no thought of giving a general account of Mr. Perkins’ researches in physical science, yet it may not be out of place to notice one or two other of his discoveries. (1) His experiments on the compressibility of water (made some time before he left America) were to test the correctness of the doctrine founded on the Florentine experiments, that water was a non-elastic body, which was then generally taught in the schools and elementary works. At that time Mr. Perkins had never heard of the experiments of Canton, (made some fifty years before) which had established the com- pressibility of water. Although by Mr. Perkins’ experiments its discovery was not strictly new yet they were of high scientific value, because of the widely different compressing forces employed by him and by Canton, the latter having applied the pressure from half an atmosphere to two atmo- spheres, say from seven and a half to thirty pounds a square inch, whilst that employed by Perkins was from fifty to four hundred atmospheres, or from 750 lbs. to 6,000 lbs. per inch. The same rate of compression appeared in all his experiments, which corresponded with that shown by Canton’s experi- ments, and in all of which the water was compressed in volume directly as the compressing forces. The apparatus employed by Perkins was first a cast iron cylinder, about three inches thick, with a movable top of equal strength ; this, filled with water, had a force pump (as in the hydraulic press) to measure the pressure within by the leverage and size of the induction pipe. 2nd. A small brass cylinder, with a piston to slide in it, water tight, about three quarters of an inch diameter, and to have a column of water ten inches long under the piston. The piston rod, graduated to divisions of a hundred to the inch, had a sliding ring on it, to be pressed upon the rod as it was forced down upon the enclosed water, thus marking in the hundreths of an inch the descent of the rod ; the brass cylinder, being under the same pressure inside and out, was not sub- ject to any strain to alter its capacity. 3rd. When the external pressure was removed, the water in the brass cylinder expanding to its original length and raising the piston rod, would of course mark the greatest compression effected. In each experiment the diminished bulk of water was directly as the pressure applied, and under the pressure of 100 atmo- spheres the bulk of the water was reduced one part in a hundred, and, as before mentioned, this rate proved to bo the 53 same as that shown by the experiments of Canton. Some time after Professor Oersted made similar experiments by employing a stout glass vessel and using a column of mercury to give the pressure, having the like inside cylinder as that of Perkins to mark the result, which confirmed the same rate as that shown by Perkins and Canton. Appendix II. On Perkins'1 Steam Gun. i Mr. Perkins conceived the idea of employing steam at a very high pressure for discharging projectiles with greater rapidity and effect than could be done by the common use of gunpowder. To effect this object he devised a plan for heating water more intensely than could be done by any boilers then known, viz. — that of employing a great number of iron or copper tubes, with their ends fastened into plates, with chambers or cavities for receiving the water at one end and emitting the steam at the other. This apparatus was placed in the midst of a furnace for the heat to act directly on the water in the tubes, and thus, as Mr. Perkins phrased it, the water could be made red hot and flash into steam with a force exceeding that of gunpowder. Then a gun barrel, with its breech opposite the valve opening from the steam chamber, and an apparatus for conducting the balls into the space between the breech of the barrel and the outlet of the steam, and, the valve opening at the same time, the steam issued and propelled the balls through the gun in rapid succession with a force about equal to common powder, which could be continued as long as the heat of the furnace could keep up the pressure. He found that from fifty to a hundred balls per minute were shot forth to a target, about one hundred yards, with a force nearly equal to that of a common musket, and of course by having ten such guns fixed to the same furnace, from 500 to 1,000 balls might be dis- charged per minute. His experiments were witnessed by the 54 Duke of Wellington and many other eminent men, who took much interest in them. The non-adoption of his system arose from several radical defects in it — first, the danger from fire of having such a cumbrous furnace on a ship ; second, the time required to get up the steam in case of sudden encounter with an enemy, which might lead to a surrender before a shot could be thrown from the steam battery ; third, by unequal heating the tubes sometimes gave way, allowing the water to escape, and though the quantity being small would not cause explosions, leaks would deaden the fire and stop the action of the guns, and any suspension in the midst of action must be fatal to the ship using such a weapon. Still the after interest attached to the plan of the tubular boilers came from reversing the scheme used by Perkins, viz employing the tubes as flues for the fire, to convey the heat through the tubes to the water surrounding, then, in an outer boiler, by this method, without damaging the tubes, it is found that high pressure steam can be employed with safety and advantage, so that Mr. Perkins’ invention was not barren to the outer world, since his tubular boilers led to their extended employment in railway and steam- boat engines, and were, I believe, first employed by Stephenson a few years after the steam gun experiments had been put “ hors de combat.” NOTE. Although it is needless to describe the process of case hardening, so generally known, it may be well to explain that of decarbonising the steel plates for engraving. This process is as follows : — The prepared steel plates are placed in a cast-iron box, and covered about an inch deep with an oxide of iron, prepared by subjecting iron filings to alternate wetting and drying until they are mostly converted into red oxide. Over this covering a clay luting is placed so as to exclude the air, and the box is then placed in a furnace and kept at a red heat for about sixty hours, when the oxide in contact with the steel will have taken up the carbon from its surface to the depth of about a sixteenth of an inch, and thus convert the surface into" pure iron, as mentioned in the text. Engraving of Mr. J. B. Dancer’s method of illuminating opaque objects under the high powers of the microscope. At A is shown a concave mirror, having a vertical and horizontal movement, mounted over the oblique body of a binocular microscope. By this mirror the light is reflected down to the Wenham’s prism, and thence through the objective to the object. Another method. B is a representation of a small speculum fixed at the end of a brass wire. This is inserted into the vertical body just over the fine motion tube at C. The speculum receives light at the side of the microscope at D, and reflects it down through the objective to the object. If there is any obstacle in the way of attaching the small speculum in the vertical body as shown at C, it could be fitted to an adapting ring -between the body and the objective. 56 PHYSICAL AND MATHEMATICAL SECTION. December 7th, 1865. E. W. Binney, F.R.S., F.G.S., President of the Section, in the Chair. A paper was read “ On the November Meteors, as observed at Woodcroft, Cuckfield, Sussex, November 12-13, 1865,” by George Knott, Esq., F.R.A.S., communicated by Joseph Baxendell, F.R.A.S. The night of November 12th being fine, Mrs. Knott and myself were enabled to watch under favourable circumstances for the meteor-shower, of which warning had been given at the last meeting of the Royal Astronomical Society. An occasional examination of the sky during the earlier part of the night did not reveal a single meteor, but as a systematic watch was not commenced before midnight, too much weight must not be attached to this circumstance. Our station commanded a clear view of the southern half of the horizon, but towards the north the view was obstructed by the’ house. Between l2h. and Ih. a.m. we counted 39 meteors, giving an average of rather more than 0 6 per minute ; the next 55m. added 6 1 to the number, giving an average of IT per minute. After half an hour’s interval we resumed our watch at 2h. 25m. a.m., and between that hour and 3h. 5m., when we ceased observing, we noted 55 meteors, showing that the average had risen to 1’4 per minute. The observations of the last 40 minutes showed clearly that the radiant point was in the immediate vicinity of the star £ Leonis, 57 or, perhaps, between that star and a and pof the same constel- lation, the neighbourhood in fact of what the Rev. C. Pritchard happily terms the “ apex of the earth’s way.” The paths of a few meteors seemed to suggest a second radiant point in the neighbourhood of /3 Tauri, but the observed flights were too few to afford satisfactory evidence on the point. We remarked a strong tendency of the meteors to occur in groups, four or five, and in some cases more, appearing one after the other in quick succession, followed by a lull, during which none were seen. We did not notice any of very remarkable brilliancy, they ranged for the most part from that of stars of the first magnitude downwards, in the majority of instances leaving a train behind them, which in several cases remained visible for some little time after the main body of the meteor had disappeared. Among such numbers it would hardly be possible, in all likelihood, to identify individuals ; I may just notice, how- ever, that at 2h. 42m. 30s. a bright meteor passed precisely over a Orionis, leaving a train which remained visible for a few seconds, on which the star had the curious appearance of being threaded. The meteor passed in the direction of y Orionis, its time of flight being about one second, and the length of its path, of which a Orionis was about the middle point, 10° or 12°. Of course, in the case of an unpractised observer, these data must of necessity be very rough, and I much regret that I was not at the time acquainted with Mr. Herschel’s ingenious alphabetic chronometer. In the last number of the Abbe Moigno’s serial “ Les Mondes,” I find the following observations by M. Coulvier-Gravier ; — “ Night of the 12-13 November. First hours of the night up to 4 a.m., 237 meteors observed, or about 29*7 per hour; from 4h. to 5h., 96 meteors, or on the average 1*6 per minute ; from 5h. to 6h., 43 meteors, or 0-7 per minute.” A comparison of these results with those of our own obser- 58 vations, would seem to indicate not only that there was no very material increase in the average number of meteors per minute as the morning advanced, but also that the display was already on the decline before daylight put an end to observation. At the same time it is to be noticed that, according to the observations of M. Coulvier-Gravier, meteors in more than average numbers, indeed very considerably so, were to be seen on the night of the 13-14 November; he observed, “ although the sky was almost constantly clouded, 72 meteors, of which 36 appeared between the hours of 4 and 6 a.m., when only 0-2 of the sky was clear.” But in any case, so“ far as present accounts are concerned, it would appear that the display this year was by no means a very extraordinary one. The position of Mr. Knott’s Observatory is Lat. 51° 0' 41" N., Long. 0°. O'. 34". W. In the discussion which ensued Mr. Thomas Heelis, F.R.A.S., pointed out the advantage first suggested by Quetelet, in 1841, of recording not only the position of the radiant point but also the mean distance from such point at which the meteors became visible ; and Mr. Baxendell con- curred in this, stating that he had himself, in the display of 1833, noted that the meteors had apparently lain in at least two strata, each stratum having its peculiar mean distance of apparition from the radiant point. Mr. Heelis also called attention to the danger which appeared to him to exist of forming a theory of meteors from observations taken from a one-sided point of view, and urged that as the observations of M. Coulvier-Gravier, in France, had led him to the conclusion that all meteors were atmo- spheric, whilst the form adopted by the British Association had been framed by a committee the members of which regarded all meteors as cosmical, each form should in the interests of truth be so far altered as to inclose, when 59 practicable, not only the particulars already noted, but also some of the atmospheric conditions, both at the time of observation and also at a given time afterwards, which Mr. Baxendell suggested should not be less than 24 hours. Exception was likewise taken to the exclusion, by the members of the committee, of small meteors from their catalogue. Mr. Baxendell added that to his mind one of the greatest objections to the cosmical theory was that the constant deposit during thousands of years of the remains of meteors upon the surface of the earth, had not altered the time of diurnal rotation. The general opinion of the section appeared to be that no one origin ought to be exclusively assigned to meteors, and that both the cosmical and atmospheric theories, if pushed to the exclusion of each other, were wrong. Mr. Baxendell referring to his paper “ On the Variable Star S Delphini” (see page 28) read the following extract of a letter he had received from Mr. Knott : — “ I was much interested in your remarks on our different modes of drawing the light-curves of variable stars. You were quite correct in your statement that I have been in the habit of regarding deviations from an even curve as due mainly to errors of observation. I have, however, recently felt that this hypothesis was not quite a satisfactory one, and have been on the point of broaching the question to you once or twice ; and the recent projection of observations of R Vulpeculse has strongly confirmed my suspicions. I enclose a projection of my observations of this star for the last maximum and minimum. You will at once see the marked dislocation in the ascending curve. An even curve would give an apparent error of observation on August 24 amounting to about half a magnitude; yet my light estimates * on that day were R Vulpeculse=e+2==/=y — 3, the magni- tudes of the comparison stars being 9'5, 9-7, and 10-0, and 60 the resulting values of the magnitude of R for the night being therefore 9*7, 9*7, 9*7. It is difficult to imagine I could have made an error of half a magnitude here ! The descending curve is, you will see, very regular. It seems to me that this is rather an interesting point in variable star observations, and worthy of some study.” The projection of the observations of R Vulpeculae referred to in this extract was exhibited to the meeting, and the general impression of the members present seemed to be that the irregularity in the ascending part of the curve could not fairly be attributed to errors of observation. 61 Ordinary Meeting, December ‘26th, 1865. R. Angus Smith, Ph.D., F.R.S., &c., President, in the Chair. Mr. Henry Simpson, M.D., was elected an Ordinary Member of the Society. Mr. Binney F.R.S., F.G.S., exhibited some singular cal- careous nodules found in the lower coal seams of Lancashire and Yorkshire, full of beautiful specimens of fossil wood, showing structure even to the smallest strise of the tubes. These nodules were found in several seams of coal, but were always associated, so far as yet known, with beds of fossil shells lying immediately above them. In one instance the beds occurred in the following descending order, namely : — Ft. In. 1. Black shale full of shells of the genera Aviculo- pecten, Goniatites, Posidonia, &c., and con- taining calcareous concretions enclosing similar shells 1 6 1. Seam of caking coal with the nodules contain- ing the fossil plants 2 0 3. Floor of fire clay and gannister, full of Stig- may'ia ficoides 2 6 The fossil wood is found in nodules dispersed throughout the coal, some being spherical, and others elongated and flat- tened ovals, varying in size from the bulk of a common pea to eight and ten inches in diameter. In some portions of the seam of coal the nodules are so numerous as to render it Proceedings— Lit. & Phil. Society — Vol. Y. — No. 7. — Session 1865-66. utterly useless, aud they will occur over a space of several acres, and then for the most part disappear aud again occur as numerous as ever. For a distance of twenty-five to thirty miles the nodules occur in this seam of coal in more or less abundance, but always, so far as yet known, containing the same plants. Fossil shells are rarely met with in the nodules found in the coal, but they occur abundantly in the large calcareous concretions found in the roof of the mine, and are there associated with Dadoxylon containing Stembergia piths, which plant had not been noticed in the coal, and Lepido- strobus. So far as his experience extended, the nodules in the coal were always found associated with the occurrence of fossil shells in the roof, and were probably owing to the pre- sence of mineral matter held in solution in water and preci- pitated upon or aggregated around certain centres in the mass of the vegetable matter now forming coal before the bituminization of such vegetables took place. No doubt such nodules contain a fair sample of the plants of which the seams of coal in which they are found were formed, and their calci- fication was most probably in a great measure due to the abundance of shells afterwards accumulated in the soft mud now forming the shale overlying the coal. These shells, on their decomposition, would yield most of the minerals now found in the fossil wood, whilst the surrounding salt water and vegetables would supply the remainder. 'The specimen of Sigillaria vascularis exhibited was of an irregular oval shape, one foot three inches in circumference, had the ribs and furrows well shown on the outside of the decorticated stem, and afforded evidence of the structure of the original plant from the centre to the circumference. In the middle was a light coloured cylinder of about an inch in diameter, which appeared to be composed of carbonate of lime and carbonate of magnesia. The remainder of the specimen was of a much darker colour. By the kindness of our Presi- dent an analysis was made in his laboratory, by Mr. Browning, 63 of a fair sample of the bulk of the dark part of the specimen. This gave Sulphates of potash and soda 1-62 Carbonate of lime 45-61 Carbonate of magnesia 26-91 Bisulphide of iron 1T65 Oxides of iron 13-578 Silica 0-23 Moisture v . . . . 0.402 The minutest vessels of the central axis and the internal radiating cylinder of the plant, with their finely striated sides, were preserved nearly as perfectly as in the living plant, without affording evidence of disarrangement from pressure or chemical change. From the position where the calcareous nodules occur, namely in the middle of the seam of coal, they must have have been formed when the coal was in a soft and pulpy state and in the same shape and condition in which they are now found, something similar to such nodules in a peat bog of the present day. Instances have been known of hazel nuts placed in a damp calcareous deposit having had all their kernels removed and replaced by carbonate of lime while the woody portion of the nutshell remained little altered, but in this case the form of the starchy granules and original cellular tissue had not been preserved. From the analysis previously given it is evident that the waters in which the nodules were formed contained a consi- derable amount of sulphuric acid, probably as much as would act on the cellular tissue and woody fibre of the vegetables so as to convert them into colloids. If this be assumed to be the case, then we might by the laws of liquid diffusion given by Mr. Thomas Graham, F.R.S., Master of the Mint, in his valuable paper printed in the Philosophical Transactions for T86 1 , suppose that the crystalloids now forming the light coloured cylinder in the middle of the specimen could have a 64 free passage from the circumference to the centre, and replace molecule by molecule the particles of the original vegetable, and all its beautiful and delicate structure just as we now see it preserved in the stone. However, before dialysis could be held to account satisfactorily for the phenomena above stated, a good many experiments on recent woods would have to be made, and more attention devoted to the subject than he (Mr. Binney) would be able to give. The specimens ’exhibited were a portion of those described in a paper in the Philosophical Transactions of this year. MICROSCOPICAL AND NATURAL HISTORY SECTIONS. December 18 th, 1865. J. B. Dancer, F.R.A.S., in the Chair. Mr. Parry exhibited some sections of fossil wood and Echinus spines, most beautifully cut by Mr. John Butter- worth, of Oldham, and presented some of the slides to the Section. Mr. Parry also presented to the meeting, for distribution among the members, mounted slides of the contents of a shark’s stomach, from the Madras coast, consisting almost entirely of Diatomaceae. Mr. Hurst then made a few remarks on late improve- ments in illuminating opaque objects under the higher powers of the microscope. He said they consisted ot three different methods. Firstly, that of H. E. Smith, of Kenyon College, America, described in the “ English ” Mechanics’’ Magazine of the 20th October, 1865, in an extract from the American Journal of Science and Arts. This gentleman employed a box, or adaptor, between the object glass and the 65 Wenham’s Prism of the binocular, with a side perforation opposite to which was a small silver reflector or a common thin glass cover, acting as a mirror and capable of adjustment to any angle — thus enabling it to throw the rays of light admitted by the side aperture through the object glass down on to the object itself. The disadvantage of this method is that all adaptors cause unsteadiness, and however skilfully constructed injure the accurate centering of the object glass, and while on the one hand the thin glass cover appears to produce some distortion of the image, the reflector so near the object necessarily casts off a number of the rays proceeding from it. This plan also seems to require lamp light and the use of a condenser. Messrs. Smith and Beck appear to have patented the use of the thin glass cover. Secondly, a modification of the foregoing by Mr. Dancer, of this Section, who places the thin glass or reflector between the eyepiece and the Wenharn prism, cutting an aperture in the body of the microscope to admit the light. This dis- penses with the objection inherent to adaptors, and theoreti- cally seems the most perfect of these new methods ; but Mr. Hurst’s experience in its use was as yet too limited to form an opinion. He hoped however to report on the subject at the next meeting. Thirdly, that invented by Mr. Dancer, who places a circular mirror over the oblique tube of the microscope, previously removing the eye piece : the light is thrown down to the Wenham’s prism, and thence through the objective on to the object. The only disadvantage of this method was that of not admitting of binocular vision ; otherwise its simplicity, cheapness, and great facility of adjustment render it far "preferable to the others, while its effects are fully equal to theirs. It answers moreover equally well by day or lamp light, and does not require a condenser, to be used. Mr. Hurst thought every binocular microscope 66 would be fitted with it when their owners had seen its working. Mr. Hurst wished meanwhile to draw the particular atten- tion of the members to the extraordinary beauty and clear- ness with which opaque objects — hitherto the despair of microscopists — were displayed by these methods of illumina- tion, some being shown as clearly as if enlarged into a rela- tively gigantic model and viewed by the naked eye. Another peculiarity connected with them is, that as the object glass itself acts as a condenser, the amount of light is increased with the magnifying power of the object glass, contrary to the effect of other modes of illumination. Mr. Hurst thought the subject was in its infancy and that great improvements would yet be made, but that the idea of Mr. H. E. Smith, of making the object glass its own illumi- nator, would prove to be one of the greatest steps in modern microscopic science, and, as improved upon by Mr. Dancer, it was one so costless in price and rapid in its adjustment that every microscopist, however economical either of time or money, could readily avail of its assistance. Mr. Coward then exhibited some interesting plants from India, illustrating abnormal forms of different natural fami- lies, especially of Leguminosese. 67 Ordinary Meeting, January 9th, 1866. R. Angus Smith, Ph.D., F.R.S., &c., President, in the Chair. Mr. Eddowes Bowman, M.A., gave an extended series of striking illustrations of the principal phenomena of polarised light. PHOTOGRAPHICAL SECTION. December 14th, 1865. J. P. Joule, LL.D., F.R.S., Vice-President of the Section, in the Chair. Mr. Joseph Sidebotham read a paper “ On the Applica- tion of Measuring Rods to Photographic Pictures.” The author referred to a paper on this subject read last Session ( Proceedings , vol. iv , p. 115), in which he advocated the use of graduated rods being placed in certain positions in buildings or landscapes of which photographs were to be taken, whereby correct measurements might be afterwards made on the finished picture. Pie now briefly alluded to certain corrections which would be necessary before these measurements could be considered perfectly accurate. Pbooeedings— Lit. & Phil. Society— Vol. V.— No. 8.— Session 1865-66. 68 Professor C. Piazzi Smyth had made great use of this plan during his investigations at the great pyramid last winter, and had kindly allowed a selection of forty of his pictures to be exhibited to the members as illustrations. The pictures were exhibited by the oxyhydrogen light on the screen, and were admirable photographs. They consisted of a series of views of the exterior and interior of the tomb of King Shafra, recently excavated near the great sphynx. A series of four of these, taken to show the correct orientation of one of the passages, are very remarkable, having been taken two minutes before twelve, twelve o’clock, and two minutes past, true astronomical time. Views were also exhibited of the entrance to the great pyramid, the socket in which the corner stone had rested, also views of the niche in Queen’s Chamber, and the mysterious coffer in the so-called King’s Chamber, the object of so much interest and speculation. These interior views were taken by the aid of the magnesium light, and, considering the many difficulties to be overcome, are very good photographs. The divisions on the measuring rods surrounding the coffer are exceedingly plain, and by the application of a pair of compasses a tolerably correct measure- ment may be obtained. A paper was then read “ On Celestial Photography,” by A. Brothers, F.R.A.S. The credit of having produced the first photograph of a celestial object is generally given to the late Mr. Bond, of Cambridge, U.S.; but it appears from a paper by Professor H. Draper, of New York, published in April, 1864, that in the year 1840 his father, Dr. J. W. Draper, was the first who succeeded in photographing the moon. Dr. Draper states that at the time named (1840), “it was generally supposed the moon’s light contained no actinic rays, and was entirely without effect on the sensitive silver compounds used in Daguerreotyping.” With a telescope of five inches 69 aperture Dr. Draper obtained pictures on silver plates, and presented them to the Lyceum of Natural History of New York. Daguerre is stated to have made an unsuccessful attempt to photograph the moon, but I have been unable to ascertain when this experiment was made. Mr. Bond’s photographs of the moon were made in 1850. The telescope used by him was the Cambridge (U.S.) refrac- tor of fifteen inches aperture, which gave an image of the moon at the focus of the object glass two inches in diameter. Daguerreotypes and pictures on glass mounted for the stereo- scope were thus obtained, and some of them were shown at the Great Exhibition of 1851, in London. Mr. Bond also proved the advantage to be derived from photographs of double stars, and found that their distances could be measured on the plate with results agreeing well with those obtained by direct measurement with the micrometer. Between the years 1850 and 1857 we find the names of Father Secchi in Home, and MM. Berch and Arnauld in France ; and in England, Professor Phillips, Mr. Hartnup, Mr. Crookes, Mr. De la Rue, Mr. Fry, and Mr. Huggins. To these may be added the name of Mr. Dancer, of Man- chester, who, in February, 1852, made some negatives of the moon with a four and a-quarter inch object glass. They were small, but of such excellence that they Avould bear examination under the microscope with a three-inch objective, and they are believed to be the first ever taken in this country. Mr. Baxendell and Mr. Williamson, also of Manchester, were engaged about the same time in producing photographs of the moon. The first detailed account of experiments in celestial photography which I have met with is by Professor Phillips, who read a paper on the subject at the meeting of the British Association at Hull in 1853. Professor Phillips says : — “If photography can ever succeed in portraying as much of the moon as the eye can see and discriminate, we shall be able to 70 leave to future times monuments by which the secular changes of the moon’s physical aspect may be determined. And if this be impracticable — if the utmost success of the photographer should only produce a picture of the larger features of the moon, this will be a gift of the highest value, since it will be a basis, an accurate and practical foundation of the minuter details, which, with such aid, the artist may confidently sketch.” The pictures of the moon taken by Professor Phillips were made with a six and a-quarter inch refractor by Cooke. It is of eleven feet focus, and produces a negative of one and a- quarter inches diameter, in thirty seconds. Professor Phillips does not enter very minutely into the photographic part of the subject, but he gives some very useful details of calcula- tions as to what may be expected to be seen in photographs taken with such a splendid instrument as that of Lord Rosse. It is assumed that an image of the moon may be obtained direct of twelve inches diameter, and this when again magni- fied sufficiently would show “ black bands twelve yards across.” What may be done remains to be seen, but up to the present time the Professor’s anticipations have not been realised. W e have next, from the pen of Mr. Crookes, a paper com- municated to the Royal Society of London, in December, 1856, but which was not read before that society until February in the following year. Mr. Crookes appears to have obtained good results as early as 1855, and, assisted by a grant from the Donation Fund of the Royal Society, he was enabled to give attention to the subject during the greater part of the year following. The details of the process em- ployed are given in the paper with much minuteness. The telescope used was the equatorial refractor at the Liverpool Observatory, of eight inches aperture, and twelve and a-half feet focal length, producing an image of the moon L35 inch diameter. The body of a small camera was fixed in the place of the eyepiece, so that the image of the moon was received 71 in the usual way on the ground glass. The chemical focus of the object glass was found to be eight-tenths of an inch beyond the optical focus, being over-corrected for the actinic rays. Although a good clock movement driven by water power is applied to the telescope, it was found necessary to follow the moon’s motions by means of the slow-motion handles attached to the right ascension and declination circles, and this was effected by using an eyepiece, with a power of 200 on the finder, keeping the cross-wires steadily on one spot. With this instrument Mr. Hartnup had taken a large number of negatives, but owing to the long exposure required he was not successful ; but with more suitable col- lodion and chemical solutions, and although the temperature of the observatory was below the freezing point, Mr. Crookes obtained dense negatives in about four seconds. Mr. Crookes afterwards enlarged his negatives twenty diameters, and he expresses his opinion that the magnifying should be con- ducted simultaneously with the photography by having a proper arrangement of lenses, so as to throw an enlarged image of the moon at once on the collodion plate ; and he states that the want of light could be no objection, as an ex- posure of from two to ten minutes would not be “ too severe a tax upon a steady and skilful hand and eye.” In an appendix to his paper Mr. Crookes gives some par- ticulars as to the time required to obtain negatives of the moon with different telescopes, from which it appears that the time varied from six minutes to six seconds. The different results named must, I conclude, have been caused not so much by the differences in the instruments as in the various processes employed, and in the manipulation. I must ob- serve, also, that it is not stated whether all the experiments were tried upon the full moon, a point materially affecting the time. ' Mr. Grubb read a paper on this subject before the Dublin Photographic Society on May 6th, 1857. After referring to 72 the fact that he found the actinic focus of his object glass to be longer than the visual (thus agreeing with Mr. Crookes) he states it to be generally understood that in a compound object-glass made as nearly achromatic as possible, the actinic focus is shorter than the visual. The most valuable portion of Mr. Grubb’s paper is the suggestion for a piece of appa- ratus to be attached to the part connected with the telescope for holding the dark frame, which he proposes may be so arranged as to follow the moon’s 'motion in declination ; and he gives the following description of a contrivance used by Lord Rosse, and which is suitable for telescopes not equa- torially mounted : — “ On a flat surface attached to the teles- cope, and parallel to the plane of the image is attached a sliding plate, the slide being capable of adjustment to the direction of the moon’s path at the time of operating. The slide is actuated by a screw moved by clockwork, and having a governor or regulator of peculiar construction, which acts equally well in all positions. The clockwork being once adjusted requires no change ; but the inclination of the slide must be effected by trial for the moon’s path at the time of taking the photograph.” This idea originated with Mr. De la Rue, Lord Rosse’s share in it arose from his having applied a clock motion to the apparatus. The telescope used by Mr. Grubb is l&flo inches aperture and twenty feet focus, giving an image 2tV inches diameter in from ten to forty seconds. The next contribution on this subject is by Mr. Fry, who, in 1857, commenced his experiments on the moon with an equatorial telescope, the property of Mr. Howell, of Brighton. The object glass of this instrument is eight and a-half inches diameter and eleven feet focus, and gave an image of the full moon in about three seconds, but under very favourable circumstances a negative was made in a single second. The size of the image is not stated, but it must have been about one and a-quarter inches diameter. Mr. Fry appears to have 73 removed the eyepiece of the telescope, and in its place a board was fixed having a screw adjustment, so that a plate- holder could be moved backwards and forwards on the board (graduated to tenths of an inch) for the purpose of finding the actinic focus, which was three quarters of an inch beyond the visual. He found that this position of the chemical focus was variable, owing, as he thought, to the varying distance of the moon from the earth, but, as suggested by Mr. De la Rue, it might arise from the length of the telescope tube having altered through change of temperature. In 1858 Mr. De la Rue read an important paper before the Royal Astronomical Society, from which it appears that the light of the moon is from two to three times brighter than Jupiter, while its actinic power is only as six to five, or six to four. On December 7th, 1857, Jupiter was photographed in five seconds and Saturn in one minute, and on another occasion the moon and Saturn were photographed just after an occultation of the planet in fifteen seconds. The report of the council of the Royal Astronomical Society for 1858 contains the following remarks: — “ A very curious result, since to some extent confirmed by Professor Secchi, has been pointed out by Mr. De la Rue, namely, that those portions of the moon’s surface which are illuminated by a very oblique ray from the sun possesses so little photogenic power, that, although to the eye they appear as bright as other portions of the moon illuminated by a more direct ray, the latter will produce the effect called by photo- graphers, solarisation, before the former (the obliquely-illu- minated portions) can produce the faintest image.” And the report also suggests that the moon may have a comparatively dense atmosphere, and that there may be vege- tation on those parts called seas. At the meeting of the British Association at Aberdeen, in 1859, Mr. De la Rue read a very valuable paper on celestial photography. An abstract of this paper was published at the 74 time in The British Journal of Photography, and in August and September of the following year further details of Mr. De la Rue’s method of working were given in the same Journal. The processes and machinery employed are so minutely described that it is unnecessary here to say more than that Mr. De la Rue commenced his experiments about the end of 1852, and that he used a reflecting telescope of his own manufacture of thirteen inches aperture and ten feet focal length, which gives a negative of the moon averaging about lp^th of an inch in diameter. The photographs were at first taken at the side of the tube after the image had been twice reflected. This was afterwards altered so as to allow the image to pass direct to the collodion plate, but the ad- vantage gained by this method was not so satisfactory as was expected. In taking pictures at the side of the tube, a small camera box was fixed in the place of the eyepiece, and at the back a small compound microscope was attached, so that the edge of a broad wire was always kept in contact with one of the craters on the moon’s surface, the image being seen through the collodion film at the same time with the wire in the focus of the microscope. This ingenious contrivance in the absence of a driving clock was found to be very effectual, and some very sharp and beautiful negatives were thus ob- tained. Mr. De la Rue afterwards applied a clockwork motion to the telescope, and his negatives taken with the same instrument are as yet the best ever obtained in this country. The advantage of the reflecting over the refracting telescope is very great, owing to the coincidence of the visual and actinic foci, but it will presently appear that the refractor can be made to equal if not excel the work of the reflector. Mr. De la Rue's paper (as published in the report of the British Association,) contains some extremely interesting particulars as to the mode of obtaining stereoscopic pictures of the moon, and diagrams are given showing the effects of the moon’s libration. Tlie most beautiful stereoscopic prints of the moon are those by Mr. De la Hue. Mr. Fry also was very successful in this branch of celestial photography. In this brief history of the subject of celestial photography, I have not referred to anything which has been done in making photographs of the solar spots, but the matter must not be altogether passed over. The first step in this direction appears to have been taken in France, in 1845, by MM. Fizeau and Foucault, but it is chiefly due to the efforts of Mr. De la Hue that so much useful work has been done in heliography. In 1860 Mr. De la Rue and Iris staff of assist- ants performed one of the greatest feats yet recorded in this branch of the art. of photography, having succeeded in obtaining several beautiful negatives of the various phenomena seen only during total eclipses of the sun, and two negatives were obtained during the. totality. One question of much interest to astronomers was determined by this great experi- ment. The red prominences or flames generally seen as issuing from the edge of the moon were proved to belong to the sun. Photographs of the sun are taken daily when the weather is favourable at the Kew Observatory, and also by Professor Selwyn, at Ely. With the Kew photoheliograph pictures of the sun spots have been made on the scale of three feet to the sun’s diameter. Much, however, remains to be done. The light of thesun is much in excess of what is required to obtain a collodion picture, so that the loss of light consequent on the necessary interposition of lenses and the distance of the plate from the instrument can be no objection ; and for these reasons I have very little doubt that with apparatus suitably arranged photographs of spots and groups of spots will be obtained of very much larger diameter than any yet taken. The Quarterly Journal of Science for April, 1864, contains -the next important paper on celestial photography. It is by Dr. Henry Draper, one of the Professors at the New York 76 University. On his return to America, after paying a visit to Parsonstown, where he had the advantage not only of making some observations with Lord Rosse’s large reflector, but also of seeing the method there pursued in grinding and polishing mirrors, stimulated by what he had seen, it was determined to build an observatory, and to construct an instrument to be devoted solely to celestial photography. The speculum used by Dr. Draper is fifteen and a-half inches in diameter, and twelve and a-half feet focal length ; but this was afterwards superseded by one of glass on Foucault’s principle. The great labour involved in a work of this character may be judged of by the fact that Dr. Draper ground and polished more than 100 mirrors, varying in diameter from nineteen inches to a quarter of an inch ; but he appears at last to have secured a good instrument. The chief points to be noticed in this article are, that instead of driving the telescope in the usual way by means of a clock, the frame carrying the glass plate was made to move on the plan previously referred to. Instead of clockwork to effect this motion, an instrument called a “ clepsydra” was used. It has a weight and a piston rod, which fits into the cylinder filled with water, which is allowed to escape by means of a stopcock, and can be regulated with great exactness, so as to follow the object. The large number of 1,500 negatives are stated to have been taken at this observatory, some of which would bear magnifying twenty- five diameters (the paper says times, but I assume this to be an error, as a negative must be very bad if it will not bear more than five diameters, or twenty-five times.) As the average size of the negatives was IrV inch, an increase of twenty-five diameters would give an image of the moon nearly three feet in diameter. I have not seen the prints from these negatives, and have never heard anything of the quality of the work produced by this telescope ; but it may be stated that Dr. Draper writes as if the negatives were of the best quality, and encourages others to follow his example. 77 Nearly a quarter of a century has elapsed since the moon was first photographed in America, and our friends on that side of the Atlantic have not been idle in the interval. To an American gentleman we are indebted for the best pictures of our satellite yet produced, and it is difficult to conceive that anything superior can ever be obtained ; and yet with the fact before us that Mr. De la Rue’s are better than any others taken in this country, so it may prove that even the marvel- lous pictures by Mr. Rutherford may be surpassed. Mr. Rutherford appears, from a paper in the American Journal of Science for May of the present year, to have begun his work in lunar photography in 1858 with an equatorial of eleven-and-a-quarter inches aperture, and fourteen feet focal length, and corrected in the usual way for the visual focus only. The actinic focus was found to be seven-tenths of an inch longer than the visual. The instrument gave pictures of the moon, and of the stars down to the fifth magnitude, satisfactory when compared with what had previously been done, but did not satisfy Mr. Rutherford, who, after trying to correct for the photographic ray by working with combina- tions of lenses inserted in the tube between the object glass and sensitive plate, commenced some experiments in 1861 with a silvered mirror of thirteen inches diameter, which was mounted in a frame and strapped to the tube of the refractor. Mr. Rutherford enumerates several objections to the reflector for this kind of work, but admits the advantage of the coinci- dence of foci. The reflector was abandoned and a refractor specially constructed of the same size as the first one, and nearly of the same focal length, but corrected only for the chemical ray. This glass was completed in December last, but it was not until March 6th of the present year that a sufficiently clear atmosphere occurred, and on that night the negative was taken from which the prints were made, and 'through the kindness of Dr. Roscoe I now have the pleasure of showing them to you. 78 I have entered somewhat minutely into particulars of what has been done in this branch of our favourite art, in order that we may have before us a kind of summary or index of the work done up to the present time, so that those who desire further information may at once refer to the authori- ties quoted. It may be asked why it was thought necessary to draw up this paper, as Mr, Ue la llue and others have said almost all that is necessary to enable anyone to take up the subject and to pursue it sucessfully. It is true there are very elaborate papers, and from their perusal I have derived much useful information, but at the same time it must be confessed their very elaborateness de- terred me, for a long time after I possessed the necessary apparatus, from commencing the experiments which have since afforded me so much enjoyment. Every writer on this subject speaks of the difficulties encountered from optical, instrumental, and atmospheric causes ; and to this may be attributed the fact that we have so few of our amateur astronomers giving their attention to the subject. Another reason may be that comparatively few of those who possess telescopes may have the necessary pho- tographic knowledge ; but surely some friend having this knowledge might be found who would be willing to spare a few hours occasionally to assist in taking negatives of the stars, planets, or of the moon. The reason, then, why this subject is brought before your notice this evening is, that it is believed that the apparatus I use is, in some particulars, more simple than any heretofore described, and as it can be used with any kind of telescope, a greater number of ama- teurs than are now engaged in it may be induced to follow this fascinating branch of photography. It will have been noticed that when particulars of the apparatus have been given the writer has spoken of a small camera, which has been fixed at the eye piece end of the tele- scope. As to how this was effected 1 have seen no description, CELESTIAL PHOTOCRAPHY. s; 0 < or 1 CL < in UrttutTi K TArtfytlvrh arrra^M *<£ Av A. BROTHERS, •ff'insA.mtfer . 79 and as no camera box is required I need not enter into any supposition as to the mode in which it may be done. Before deciding what was necessary to be done, it occurred to me that the telescope tube itself is the camera, and all that was required was the means of fixing the dark frame or plate holder. If the telescope be pointed to the moon, the eye piece removed, and a piece of ground glass held between the eye and the aperture, the image will be seen on the glass, and we require then the means of holding the sensitive plate steadily near the same place. All that is needed is a brass tube about four or five inches long, of the size exactly fitting the tubo of the telescope in the place of the eyepiece. In some cases the sliding tube of the eyepiece may be unscrewed and used for this purpose. At one end of this tube a thread is cut and is made to screw into a pipce of metal plate (in the centre of which is a circular aperture of the same size as the tube), of the same dimensions as the dark frame. Attached to the plate holder are clips accurately fitting the brass plate, but so that the frame will easly slide off and on without dis- turbing the telescope. This is all the additional apparatus required to enable photographs of the moon or any other celestial object to be made. A separate frame for the ground glass is not necessary : it must be cut to fit the dark frame, and while in use can be held by slight springs fixed inside the frame at the sides. The accompanying photo-lithographed copy of a drawing shows the arrangement of the apparatus when in its place for taking a negative, and renders further description unneces- sary. '1 he method for ascertaining the actinic focus may be stated in a few words. With the rack motion adjust the focus for distinct vision on the ground glass, and then mark ithe tube E, and also the sliding part of the telescope. Al- though very unlikely to be of the slightest use, unless taken with a reflecting telescope, a picture may now be taken; it will at least serve to give some idea of the proper exposure. 80 If the chemical and visual foci are not coincident the image will have a blurred appearance. Before exposing the next plate, turn the adjusting screw so as to lengthen the tube about the 16th of an inch, and so proceed until, by the greater distinctness of the image, it is seen that the chemical focus is found. At every change of the focus a slight mark should be made on the tube, and rvhen the true focus is satis- factorily determined the marks should be made distinctly visible; and in all future experiments with the same instru- ment the focus will be always at or very near the same place. Should it be found that the indistinctness increases, it will of course be necessary to try in the other direction. The appearances arising from atmospheric disturbances are very much the same as when the object is out of focus : expe- rience alone will enable the operator to determine from which cause the defect proceeds. It is assumed that the telescope is provided with a driving- clock ; when such is the case every care should be taken that all the parts are clean, and when necessary oiled or greased, so that the motions may be as smooth as possible. In photographs of the moon in the phases, prior to and after the full, the side opposite to the sun is always too light, or “ burnt up,” while those parts near the terminator are often so dark that only the tops of the craters and peaks are visible, although in the telescope a clear and bright image can be seen. The cause of this must be that the exposure, if con- tinued long enough to bring out all the eye can see on the darker side, would entirely obliterate the details on the brightly illuminated portions of the moon’s surface. Mr. De la Hue’s suggestion as to why the dark side of the moon has so little actinic effect, lias been already referred to. I would suggest that, as the light of the full moon is 100,000 times weaker than that of the sun, the twilight* on the moon’s * In the absence of an atmosphere on the moon there can be no twilight such as we have on the earth. The meaning, therefore, of this sontonee matv 81 surface must be very much less, and consequently the actinic effect of the light is lessened in the same wav as at a corre- sponding time on the earth. The question, then, of photographing the terminator is only one of time, and in order to remedy the defect spoken of to some extent, I have used diaphragms such as are shown in the drawing. In the tube E openings are made on opposite sides, and wide enough to admit the diaphragms to be used without touching the tube. The diaphragm must be of the proper length and width to shut off the moon’s light until the plate is ready for exposure. The shape of the diaphragm will suggest which form should be used according to the moon’s age. The exposure should be made with the full aperture for as many seconds as previous experiments have proved to be necessary for the bright side, and the diaphragm then gently moved and kept in motion, gradually approaching the darkened side. By this means the exposure may be regulated, and the great differences in the light and dark sides of the moon may be modified. As to the processes employed, each experimenter must adopt the one he finds in his hands gives the best result. It seldom happens that two operators can produce the same effects with, apparently , the same chemicals. Experience has shown me that the ordinary patent plate glass (carefully selected, so as to be free from scratches and other defects,) is preferable to the white patent plate, having found that after a time the surface becomes covered with a kind of dew or “ sweat,” as it is termed, owing to the decomposition of some of the salts used in the manufacture. The collodion used was made for me by Messrs. Huggon and Co. of Leeds ; it is very quick, free from structure, and suitable for iron development. be misunderstood. It was intended to say that on those parts of the moon, enlightened only by the oblique rays of the sun, the light is so diminished that the actinic effect is lessened as it is on the earth shortly before sunset and during twilight, when it is well known that a much longer time is required to obtain a photograph. 82 I prefer to develope with an iron solution, using only suffi- cient to cover the plate ; and with this developer and collodion, when the plate has been properly exposed, a negative can be obtained which will not require intensifying afterwards. Not having had sufficient experience with pyrogallic acid I cannot speak with confidence as to any advantage it may possess in giving fine texture to the negative. With the bath and collodion exactly in the proper state, there is no doubt that with this acid negatives may be had as quickly as with iron ; but it is extremely difficult to have everything constantly in the best working order. Unless the greatest attention be given to this matter, the time of exposure is so much increased that iron, for this reason, must have the preference. Upon the character of the image after development entirely depends the value of the enlargement to be made from it, and in this direction there is much room for improvement. Even in the best negatives )et made defects from this cause are very apparent. The microscopic photographs by Mr. Dancer have the finest texture, and will consequently bear greater magnify- ing than any other photographs I have ever seen, but the process by which they are made is not published. The weather in this country is so very uncertain, and suc- cess in this branch of photography is so entirely dependent on the state of the atmosphere, that it is necessary to be always prepared to take advantage of a favourable night. I have a small cupboard placed in a convenient part of my house where there is a supply of water, and the temperature is always much above the air outside. This cupboard is just large enough to hold a small glass bath fixed at the proper- angle ready for use, also the bottles for collodion, bath, developing and fixing solutions, and other little requisites. This arrangement is so convenient that when there is a pros- pect of getting a negative I can set the telescope, prepare the plate, and take a negative in less than ten minutes. But when there is a chance of two or three hours’ work an assistant is desirable, as the best results can only be obtained when one’s attention is chiefly devoted to the careful adjust- ment of the apparatus connected with the telescope. The convenience of the plan adopted may be judged of by the fact that on the evening of the partial eclipse of the moon, the 4th October last, in four hours I succeeded with the help of two assistants in taking no less than twenty negatives, and the telescope was several times disturbed to oblige friends who desired to see the progress of the eclipse through the in- strument, but the apparatus was quickly re-adjusted, although possibly in some cases with slight loss of definition in the negative, through haste. At a previous meeting, I described how these negatives were made, but it may be interesting to refer to the fact that while the fifteenth of the series was taken the telescope was at rest. The clock had been discon- nected for re-adjustment and it was forgotten when the plate was ready for exposure, consequently the moon had moved partly off the plate, and the negative shows a portion only ; but the exposure was so short that the eye fails to detect any difference in the sharpness of this and the others, which were all taken when the clock had been watched and carefully regulated for the moon’s motion. This fact is, I think, of some interest, as it shows that about the time of full moon when the light is of the greatest intensity, pictures may be made with telescopes not equatorially mounted. My telescope is a refractor of five inches aperture and six feet focal length, giving an image of the moon averaging about eleven sixteenths of an inch in diameter. The actinic focus is one tenth of an inch longer than the visual. The object glass is of Munich manufacture, and is mounted by Mr. Dancer on the Sisson’s or English plan with double polar axis. The hour circle is twenty-six inches in diameter, and is used also as the driving wheel, having teeth cut in the jedge, in which a screw works connected with the driving clock 'by a rod, and which can be instantly disconnected by means of a cam. The object glass is an excellent one, and the mounting is everything that can be desired. 84 The negative taken direct in the telescope is but one step towards what we require, that is, the enlarged copy on paper. From the small negative a positive on glass must be made, say of twice or three times the diameter of the original. It will be quite unnecessary here to explain how the enlarge- ment is to be made; but I may remark that the negative should be placed with the film side towards the copying lens, and the resulting positive copy must also be placed in the same way. The enlarged copy or negative will then give the true telescopic appearance of the moon. In the print of the full moon by Mr. Rutherford a mistake has been made, arising from the negative or positive copy having been placed the wrong way, and consequently the moon looks as if it had been photographed from the opposite side. The print is a very beautiful one in other particulars, but entirely worthless as a picture of the moon, as the eye can never see it as there represented. I have sometimes taken two negatives on the same plate. It will be seen in the drawing that the dark slide is not quite central with the telescope, so that by reversing the plate after one exposure a second picture can be taken. In photograph- ing the planets Mr. De la Rue has allowed the object to move on for a few seconds, the telescope meanwhile being at rest, and thus four or five negatives can be taken in a very short time on the same plate. It has occurred to me that by having a frame made “ landscape way” instead of upright, and in place of having four clips such as K, there might be a kind of groove at top and bottom, so that after taking the first negative, and the light shut off, by moving the plate about an inch, at least three negatives might be taken on the same plate — or a “ shifting back” might he adapted. The advan- tages of this plan are that different exposures might be tried, and the development continued for the one or two which promised the best results. This method would effect a great saving of time, which on a fine night is of much importance. With the Barlow lens I have made some negatives which 85 have shown that when the same care has been taken to find the actinic focus negatives of a much larger size may be made, and in a very short time. The image is increased from eleven- sixteenths to one and a quarter inch, and the time ot exposure at full moon was two seconds. The fittings of the lens are so arranged that three different sized negatives may he taken. There are several other matters which it might have been desirable to refer to had time permitted, but they must stand over to a future occasion. Mr. Baxendell said that some years ago Dr. Joule had obtained several beautiful negatives of the sun. The time of exposure was about too of a second, and the apparatus for admitting and cutting off the light was not attached to the telescope, as in the Kew heliograph, but was mounted on a separate stand. PHYSICAL AND MATHEMATICAL SECTION. January 4th, 1866. E. W. Binney, F.R.S., F.G.S., President of the Section, in the Chair. Mr. G. V. Vernon, F.R.A.S., M.B.M.S., was elected Honorary Secretary of the Section. Mr. Vernon communicated the following “ Remarks on the Barometric Disturbances during the Months of October, November, and December, 1865.” At the last meeting of the Physical Section attention was called to the great barometric disturbances in October and November of this year; and in order that their character may be seen at a glance I have drawn out my observations made twice daily in the subjoined curves. 86 The amount of oscillation in October was not remarkable for its excessive amount, but for the very sudden changes which took place towards the end of the month, say from the ‘23rd to the 31st. For November the reading was high until the 15th, when a sudden change commenced, the great depression of the 22nd showing the extremely low reading of 28-240 inches. The amount of oscillation during the first half of the month only amounted to about half an inch per week, leaving more than six inches for the amount of oscillation during the last half of the month, against an average of 5'851 inches for the last seventeen years for the entire month. The amount of oscillation for the two months of October and November for the last five years, in continuation of the values given in my paper in vol. i., 3rd series, of the Memoirs of the Society, are as follows : — OCTOBER. NOVEMBER. Year. Number of Oscillations Amount of Oscillation. Rainfall. Number of Oscillations Amount of Oscillation. Rainfall. 1861 13 Inches. 5-087 Inches. 1-230 15 Inches. 7-491 Inches. 3-878 1862 18 6-569 5035 13 5 323 1-685 1863 12 4-648 6-242 14 7-496 2-904 1861. 14 5-110 1-898 20 8-504 3-255 | 1865 14 6-361 5-005 15 7-390 2770 ; Means of 17 Years.. } 15-5 5-851 13-8 5-804 In the paper last alluded to I pointed out at page 3 that an excessive amount of rainfall was accompanied also by a large excess of barometric oscillation in every month but October, stating also that perhaps a longer period of observa- tion might remove this apparent anomaly. The last five years, however, give exactly the same abnormal values for October, as reference to tbe small table annexed will show. October, 1863, with the least barometric oscillation, had the largest rainfall out of the five years. November conforms to 87 the law, which applies to all the months but October, the table showing that generally the rainfall increased with the amount of oscillation. Of course leaving 1863 out of the question would make October conform to the rule also ; but it is these very abnormal months which are so difficult to account for, and which seem to bear out Mr. Baxendell’s suggestion of some secondary disturbing cause operating during the month of October especially. (Vide Mr. Baxen- dell’s paper on “ Periodic Disturbances of Atmospheric Pressure,” Memoirs, 3rd series, vol. i. p. 263.) The amount of oscillation in December was 5'468 inches, the oscillations being thirteen in number. This is somewhat below the average, although the month was marked by such wide barometric readings as shown by the diagram. The following Table of Rainfall for 1865 was also com- municated by Mr. Vernon. Old Trafford, Manchester. Rain gauge 3 feet above the ground, and 106 feet above the sea. Quarterly Periods. 1865. Fall in Average Differ- ences. No. of Days’ Rain- fall in 1865. Quarterly Periods. Quar- terly Periods for 72 Years. 1861. 1865. Inches. 72Years. 1865. 1864. Days. Days. Inches. Inches. Inches. Inches. Inches. Inches. C Jan. ... 3112 2-469 +0643 IS) 38 48 j Feb. . 2357 2-379 —0-022 17 r 7143 7-722 7-149 (. March. 1-674 2-301 —0-627 13 ) C April... 1-082 2-025 —0-943 8) 39 36 \ May... 3-187 2-368 +0-819 21 c 5 226 7-722 7-279 (.June .,. 0957 2-886 —1-829 7) ( July . . . 2-996 3-561 —0-565 15) 45 36 ] Aug.... 3-840 3-596 +0-244 18 c 7-502 8-063 10-357 (. Sept . . . 0-666 3-200 —2-534 3; ( Oct. ... 5'005 3-834 +1-171 20 4 49 44 ] Nov.... 2-770 3-464 —0-694 16 C 8-518 7-133 10-523 (. Dec — 0-743 3-225 —2-482 8) 171 164 28389 35-308 —6-919 153 28-389 30-640 35-308 The rainfall for 1865 has been 6919 inches below the average of the last seventy-two years, and 2251 inches 88 below the fall for 1864, which was also comparatively a dry vear. Although the first three months had about an average fall, the second three 'months had a fall greatly below the average. The same remark applies to the third and fourth quarters of the year. The fall of rain was remarkably small in June, September, and December; and it will also be seen that with the exception of the four months of January, May, August, and October, every month had a rainfall below the average. As compared with any other month, the rainfall in October was excessive. The number of days upon which rain fell was also greatly below that of many previous years. Mr. Baxendkll, F.R.A.S., read the following “Note on the Variable Star T Aquilse.” In the communication made to this Section on the 12th of November, 1863 ( Proceedings . vol, iii. p. 195), announcing the discovery, at Mr. Worthington’s observatory, of the vari- ability of T Aquilse, I gave the times of one minimum and one maximum, but was unable to give a trustworthy value of the length of the mean period. The observations which 1 have since made have however enabled me to determine with tolerable exactness the times of three more maxima and two minima, thus affording the means of ascertaining the value of the mean period within very moderate limits of error. The observed times of maximum and minimum and the corresponding magnitudes are : — Maxima. 1863 — Oct. 25 8 ’9 magnitude. 1864— Aug. 23 8-4 ditto 1865 — June 30 10 "1 ditto 1865— Nov. 22 9 -4 ditto Minima. 1863 — Aug. 24 1V3 magnitude. 1864 — June 24.. 1V2 ditto 1865 — Aug. 31 ITS ditto 89 The times of minima appear to be more irregular than those of maxima ; but the magnitudes at maximum vary more than those at minimum. As the times of maxima are evidently better suited for the determination of the mean period than those of minima, I have treated theirt in the usual way, and have obtained the following elements : — Period = 152-4 days. Epoch = 1865, January 24- 1. Calculating the times of maxima from these elements, and comparing them with the observed times, we have the follow- ing differences : — <;.— 0. days -0-1 + 1-7 -4-5 + 2-9 The greatest difference is only 4*5 days, or about one thirty-fourth of the entire period, and the mean difference is 2 3 days, or one sixty-sixth of the whole period. T Aquilse therefore belongs to the class of variables whose periods are moderately regular. The diagram which accompanies this communication shows the mean form of the light-curve of T Aquilse as derived from all the observations I have yet made. An examination of this curve has yielded the following results : — Mean magnitude at maximum = 9-20 Mean magnitude at minimum - 1 1 -20 Mean range of variation = 2-00 magnitudes Mean magnitude = 10 ‘40 Interval from minimum to maximum = 64-0 days Interval from maximum to minimum = 88-4 days Interval from minimum to mean magnitude... = 43-0 days Interval from mean magnitude to maximum... =■ 21-0 days 90 Interval from maximum to mean magnitude... = 40 ‘4 days Interval from mean magnitude to minimum... = 48-0 days Interval from mean magnitude before to mean magnitude after maximum - 61 -4 days Interv^J from mean magnitude before to mean magnitude after minimum = 91 '0 days A faint secondary maximum is indicated at 63 days after the principal maximum. Mr. Knott, F.R.A.S., lias kindly favoured me with the results of his observations of T Aquilee for the past year, and from the following comparison it will be seen that, with the exception of the time of the August minimum, they are very closely accordant with my own : — Maxima. Baxendell. Knott. June 30 — 10’1 mag. July 2 — 10-1 mag. Nov. 22 — 9-4 mag. Nov. 20 — 9 '4 mag. Minimum. Aug. 31 — 11*5 mag. Aug. 22 — 1 1 *4 mag. The place of T Aquilae for 1865 is 20h 5m 25*4s-fl5° 13-4', and the calculated times of its maxima for 1866 are April 26-3 and September 25'7. MEAN LIGHT-CURVE OF T AQUILJE, AS DERIVED FROM ALL THE OBSERVATIONS MADE AT Mr. WORTHINGTON’S Observatory during the years 1863-5. Mao. 91 January 23rd, 1866. R. Angus Smith, Pk.D., F.R.S., &c., President, in the Chair. M. le Marquis Anatole de Caligny, of Versailles, Civil Engineer, was elected a Corresponding Member of the Thomas Graham, F.R.S., &c., Master of the Mint ; A. W. Hofmann, F.R.S., &c. ; Joseph Prestvvich, F.R.S , &c. ; and Andrew Crombie Ramsay, F.R.S., &c., were elected Hono- rary Members of the Society. A conversation took place respecting the cattle plague, in the course of which Mr. Baxendell stated that the results of inquiries he had made had led him to believe that the total mortality among cattle from plague and all other diseases, during the past year, had been very little, if at all, above the average rate of the last ten years ; thus indicating that the plague had, to a great extent, displaced pleuro-pneumonia and other dangerous diseases, and that therefore no just cause at present existed for the feeling of alarm which prevailed throughout the country. A paper was read entitled “ Notes on a Section of Chat Moss, near Astley Station,” by W. Brockbank, Esq. By the kindness of ray friend Henry Mere Ormerod, Esq., I have had the opportunity of examining a section of the strata at Chat Moss, exposed in the excavations at present beiim made to obtain marl for the reclamation of the moss. O Proceedings — Lit. & Phil. Society. — Vol. V. — No. 9 — Session 1865-6. 92 A. large area has been excavated to a depth of 45 feet from the surface, down to the red rock, giving the following thick- nesses of the beds, viz. — a. Peat Moss 17ft. Oin. b. Sandy Clay or Loam 1ft. 6in. c. Boulder Clay or Till 26ft. 6in. d. Soft Red Rock Commencing with the red rock, the following particulars appeared worth recording : — d. The soft red rock forming the base of the section is the lower member of the trias. The surface of the rock was covered with water, which prevented an examination of it, but a large detached fragment was found lying upon it, which was not at all worn. c. The boulder clay or till had a thickness of 26ft. 6 in., and contained boulders in abundance. It had no parting of sand or gravel, but small patches of red sand occurred about the middle, ami of small gravel near the base. Small cubical fragments of coal were very plentiful, and many pieces of black shale. The following list of boulders was made from those found in the excavations, viz. — Greenstone. One very large boulder, much striated, and many smaller ones. The largest boulders were of this rock. Granites. Four varieties, all much waterworn ; the grey and green granites decomposed and very friable. Limestones. Dark limestone boulders plentiful, one con- taining a good specimen of “Productus Gigantens” on the unworn surface, the other side being deeply striated and much worn. Light grey limestones, much worn. Reddish limestones (permian), very little worn, and pro- nounced by the workmen to be “ Bedford limestone,” because worked at Bedford, in the neighbourhood. One fragment of this limestone occurred within four feet of the surface, and was very little worn, the corners quite sharp. 93 Red Marlstone Rock (permian), little worn. Hcematite Iron Ores (probably permian), worn into round lumps. These are eagerly sought by the workmen for “ red raddle.” They resemble the richest specimens of iron ore as found at the Patricroft workings, but are apparently much purer, and more like the hoematites of North Lancashire. Coal and Coal Shales. Abundant. The coal in small cubical fragments, but in great quantity. One fine specimen of coal shale with “ Anthracosia robusta,” well preserved, and one fine frond of “ Neuropleris.” Oval nodule of pyrites or “ Brass lump” from the coal measures. Sandstones. White sandstone boulders very frequent, containing fossils, probably calamites and sigillariae, and chiefly resembling the white sandstones of the middle coal measures. Ironstone. Nodules of claybound ironstones frequent ; one very good example with fine septaria in centre. The above list of boulders possesses some features of con- siderable interest. The granites and greenstones are very much the same as those found in the clays around Manches- ter, and which are generally supposed to have come from Cumberland and Westmoreland. These are much worn and have deep striee. The limestones are such as occur in the Pendle district, and their presence confirms the author in his belief that the current which denuded the coal of the high-lying seams of Lancashire and as far north as Ingleborough, and scattered the boulders which we find in this clay, came from the north- wards, and probably from the neighbourhood of Ingle- borough. The quantity of coal in small fragments was very remarkable, and evidences very considerable denudation of the coal measures, as also the presence of so many boulders of coal measure sandstones and shales, such as occur through- out the district lying to the north of Chat Moss. The unworn fragments of the permian limestones and marlstones is an 94 additional evidence, their outcrop being in the neighbour- hood immediately to the northwards. Mr. Ormerod informs me that the surface of the boulder clay is in ridges or long undulations, and that it frequently sinks into deep hollows, making the thickness of its moss covering very variable. b. The clay is capped by a seam 1ft. Gin. thick of loamy sand, which contains the roots and stumps of oak trees, birches, and hazels, the stumps being broken off about a foot from the surface, and the trees lying near, embedded in the moss. Leaves, branches, and hazel nuts are found in abund- ance in this thin stratum, upon which rests the moss. In an area of about a quarter of an acre laid bare by Mr. Ormerod’s excavations were found at least 200 cubic feet of oak timber, which was carted away for fuel, forming six cart loads. Some of the trees were two feet in diameter, the roots in situ in the loam. On one of the trees was found a fine specimen of a fungus attached to the stem at a foot or two above the root. It is a fungus now found growing on oak trees, “ Polyporus igni- arius,” and is in beautiful preservation, the pores being quite visible to the naked eye. It would appear as if the level valley plain on which Chat Moss now lies was formerly covered over with a forest of oaks with a dense undergrowth of birch, hazel, and other brushwood. How these trees were thrown down, and the forest became covered up by moss, is subject for speculation. It was probably a gradual decay, owing to the lowlying, undrained soil, which favoured the growth of sphagnum and of sucli fungi as we have seen attached to the oaks now found lying in the moss. The occurrence of this thin stratum of loam containing the roots of trees in situ, underlying the moss, is strikingly like the underclays containing roots of the stigmaria in the coal measures. 95 a. Peat Moss. The general thickness of the moss, as ex- posed in the excavations and drains made by Mr. Ormerod, is from 1 7 to 25 feet. In some parts of Chat Moss the thick- ness is much greater, owing to the irregularities in the sur- face of the boulder clay or other stratum forming the base of the moss. In one place a depth of at least 180 feet has been reached with boring rods, which would place it below sea level, and would point to the existence of water — possibly an inland arm of the sea — since filled up by moss. When the water is drained off, the moss is very consider- ably reduced in thickness. We measured it at two places where drains had been cut through to the loam, and where the moss had originally been 17 feet thick. It is now reduced to 8 feet, having sunk above one half. Mr. Ormerod believes he has thus lowered an area of 800 acres more than 3 feet on an average. It is quite evident from this circumstance that the bulk of the moss is very greatly influenced by the water contained in it, and it is probably from this cause that mosses are usually highest at the centres. The water can get away from the margins, but it remains in the centres and swells up the bulk. The existence of the boulder clay under Chat Moss affords a ready means for the reclamation of the surface for agricul- tural purposes. Mr. Ormerod proceeds in the first place by carrying forward deep drains down to the loam, having con- nection with the lowest outfall. These are connected by cross drains, which gradually draw off the water and leave a firm surface. The moss is then turned over by spade labour, after which it is covered with clay brought up from below at the extensive excavation which forms the subject of this paper. The land is next manured with town manure, and, being sown with clover and oats, is found to bear an excel- lent crop of oats the first year, and clover and grass crops the two years following. In this way it is expected the whole of Chat Moss will shortly be reclaimed. 96 PHOTOGRAPHICAL SECTION. January 11th, 1866. Dr. J. P. Joule, F.R.S., &c., Vice-President of the Section, in the Chair. A note from Mr. Joseph Sidebotham was read, regretting his inability to attend the meeting, and giving particulars respecting some photographs which he had recently taken with Dallmeyer’s new wide-angle lenses of five and seven inches focus. These prints were exhibited, and also one taken with an ordinary lens from the same spot, a compari- son of the two showing the great advantage of the new over the old form of lens. The time of exposure was stated to be from two minutes to thirty seconds for collodio-albumen plates at this season of the year. Professor Roscoe explained the method of meteorological registration of the chemical action of light, as described in his paper in the Philosophical Transactions of the Royal Society, which has been chosen as the Bakerian lecture for 1865. Dr. Roscoe exhibited the apparatus needed, and showed the method of manipulation adopted in order to obtain curves of daily chemical intensity. He also detailed the results which have been obtained by the employment of his method at the British Association’s observatory at Kew, during nine months of the year 1865, under the superintend- ence of the Director, Mr. Balfour Stewart, F.R.S. Dr. Joule observed that he considered Dr. Roscoe’s inves- tigations on this subject to be equal in importance to the 97 systematic registration of the variations of temperature, as the growth of corn, &c., depended as much on the chemical effect of light as on the temperature of the air. Mr. Baxendell regarded the subject as a new department in meteorology, and one likely to yield results of considerable interest and importance. Mr. Parry suggested that it was desirable to have obser- vations made at more than one station, and at a distance from Kew. Dr. Roscoe stated that he hoped in a short time to perfect apparatus for effecting the registration of the chemical changes in the light by means of self-acting apparatus, so as to lessen the labour of making the observations. It was suggested that a simple photometer would be useful to photographers working with dry plates, and Dr. Roscoe said he would endeavour to carry out the idea. 98 MICROSCOPICAL AND NATURAL HISTORY SECTIONS. January 17 th, 1866. A. G. Latham, Esq., President of the Section, in the Chair. The following donations were announced : — Roper’s Catalogue of Microscopic Works, by the Author. Kolliker’s Manual of Human Microscopic Anatomy, by the Executors of the late George Mosley, Esq. Beck on the Microscope, by the Secretary. Six slides of seeds and fungi, by the Secretary. Several slides of sections of a Cidaris from the Indian Ocean, by Mr. Parry. The Secretary reported that he had made a catalogue of the collection of microscopical objects belonging to the Section. Mr. Sidebotham remarked on the best cement to use in forming cells for fluid preparations, and stated that gold size appeared to prevent the entrance of air bubbles better than Japan varnish or Brunswick black, which latter in time became porous, and also, from the evaporation of its turpen- tine, brittle. He said he and Mr. Thwaite were perhaps the first to use this method of mounting objects, and that he possessed slides of gold size cells made in 1844, which were still quite perfect, while those lie mounted with Japan black in 1850 were most of them spoiled, and that he had again reverted to the use of gold size for the formation of the cell, using Japan varnish for its final closing only. 99 The Secret A ry said gold size remained viscid for a long time, and that if the cells formed of it were not well dried for a considerable period, or even baked in an oven, the size was very liable to “ run in” and spoil the preparation. He had re-varnished the Section’s collection with a mixture of Japan varnish and gold size, and thought the gold size would pre- vent the Japan varnish from becoming brittle or porous, while the latter would prevent the gold size from running in ; but he strongly recommended that all collections should be re-varnished every five years, and deprecated the use of covering papers on slides of fluid preparations, as it prevented this. Mr. Latham recommended the addition of a solution of india-rubber, and Mr. Parry of wax, to Japan varnish, to obviate its tendency to become porous and brittle. Mr. Heys showed a well mounted specimen of the exuvium of the larva of a Dragon Fly, and stated he found these insects were easily brought to cast off their skins by changing the water in which they were kept — if soft, to hard, and vice versa , or if muddy, to fresh. Mr. Parry exhibited mounted specimens of an Ammonite. Dr. Alcock said that among Foraminifera from Dogs Bay which he had lately mounted, he thought there were some slides likely to interest the members. Many of the deformed specimens of Lagena striata (Williamson) were very curious, and a double one, having the neck as well as the body double, deserved particular notice. He said that he was quite con- vinced the striated Lagena with a mucro at the base is not a mere sub-variety of Lagena striata, but is very distinct from it ‘ there were many specimens of it, all agreeing in their peculiar characters, and he proposed for it the varietal name of L. mucronata. The Lagena with a collar at the base of the 100 neck, described by him in a previous paper, was undoubtedly distinct from any of the named forms, and he proposed to call it Lagena antiqua. In his examinations of the Dogs Bay sand one specimen only of Lagena vulgaris typica (William- son) had occurred, though L. clavata was comparatively common. Perhaps the most interesting find was a perfect and characteristic specimen of Lagena crenata, a form lately described and figured by Parker and Jones, from Australia, but he believed not hitherto observed as British in the recent state. The very magnificent specimens of Entosolenia Melo also deserved notice, and the curious specimens of Truncatu- lina lobata with the later chambers “run wide,” and various monstrous forms of Miliolina, would be examined with interest. 101 Ordinary Meeting, February 6th, 1866. J. P. Joule, LL.D., F.R.S., &c., Vice-President, in the Chair. The Chairman adverted to the loss the Society had expe- rienced by the unexpected death of Mr. Parry, who from the period of his election in 1833 had constantly promoted the success of the meetings by his intelligence and kindly intercourse with the members. Mr. Baxendell said that it might interest some of the members of the Society, especially those who had commercial relations with India, to hear that the system of forecasting the weather, and particularly the occurrence of cyclone storms, had been introduced into that country by Mr. Pogson, the government astronomer at the Royal Observatory, Madras. The first trial was made on the 25th November last, when the indications of a distant but approaching cyclone induced Mr. Pogson to send a notice to the Governor, Sir William Dennison, who promptly despatched a number of mounted sepoys to convey the information to various officials and direct them to prepare for the coming storm. Next day, uprooted trees on shore and disabled ships in the roadstead showed that the indications had been rightly inter- preted. On the 4th December the weather had again a very Proceedings — Lit. & Phil. Society. — Vol. V. — No. 10 — Session 1865-6. 102 threatening appearance, and the officials of the Marine depart- ment ordered all the vessels in the roadstead to put to sea ; but Mr. Pogson, guided by the principles which had served him so well on the 25th November, concluded that a cyclone was passing far to the south, but would not approach suffi- ciently near to cause a severe gale at Madras, and he there- fore ventured to send the message, “ No need, the storm will not come here,” and the result fully justified the confi- dence he had placed in his conclusions, as the storm passed without the wind at Madras attaining a dangerous force, and unusual precautions proved therefore to be unnecessary. A paper was read entitled “ Notes on the Origin of several Mechanical Inventions, and their subsequent application to different purposes.” Part III. By J. C. Dyer, Esq., V.P. On Nail Making by Machinery. About the beginning of this century the great consumption of nails in America, in wood buildings, and the high rate of skilled labour, had led to many attempts to make nails by a more summary process than that of the hammer and anvil, used for making those imported from England. Those called “ cut nails,” were made by cutting angular slips from iron plates by the common shears, and the heads were made by a separate process of the die and hammer, worked by hand ; and to unite these two operations in one machine was the object sought. For this purpose a machine was invented and patented by Mr. J. Odiorne, and another machine by Mr. Jacob Perkins, about the year 1806. These two patents, though for the same object, differed so far in construction 103 that they were held to be distinct inventions. A third machine was invented by a Mr. Reed, which, however, was a combination of the former two, and I believe was not held valid as a patent. In 1810, Messrs. Wells and Co., of the Charles River Iron Works, near Boston, having arranged with the patentees, sent out models of the nail machine to me in London, to be patented for our joint account. The operations of the machines were as follow : — 1st. Feeding-plates, of the width and thickness to form the nails, are pushed endwise over a fixed cutter, against a stop under the traversing cutter, and at such angle with the line of the cutters as to give the severed nail the head and point ends, and the plates turned over between each suc- cessive cut. 2nd. A fixed gripping die is placed just under the fixed cutter, the face of it and the cutter being in the same line, and the counter die moves forward to bring both together, so as to hold the nails firmly, a portion of the large end standing out beyond the dies to form the heads of the nails. 3rd. The heading die then advances and presses the end into the “ rose,” “ clasp,” or “clout” heads. Success or failure often depends upon slight changes in power-driven machines. These nail machines answered very well for large nails, but failed as applied to very small ones, but as a means of saving the labour applied to making tacks and very small nails, it became important to adapt the machines to them also. This object, after some time, I suc- ceeded in accomplishing, and thereby rendered the patent nail manufactory, established under the patents for the original invention and the improvements on it, a success. 104 For a full description of these inventions I must refer to the specifications of the patents, and to the paper in extenso, as they could not be made intelligible within the limits of this abstract. The average rate of working was about 100 per minute for nails and 120 per minute for tacks. In after practise the tack machines averaged about 80,000 a day, whilst the best hand-workers made about 1,200 to 1,400 a day. Each machine was tended by a youth, much like those employed in hand-making, so that one hand with the machine turned out as many tacks per day as would require about sixty hands working with hammer and anvil. I have been informed that the speed of these machines has been greatly increased of late years. Some of the movements in these nail machines have since been adopted and found very efficient in rivetting machines and others of recent invention. 105 MICROSCOPICAL AND NATURAL HISTORY SECTIONS. January 29th, 1866. J. Sidebotham, Esq., in the Chair. The following specimens were exhibited : — Two figures of the gills of fungi on glass, made by the dropping of their spores, by Sir J. Herschel, exhibited by Mr. Sidebotham; also similar ones prepared by Mr. Sidebothain. Small cyclophorus-like shells, with a considerable part of the later growth free and strangely contorted, from Borneo, Mr. Sidebotham. Leaves of some Indian plants, mounted for the micro- scope, Mr. Hurst. Mounted Foraminifera, from shore sand, Port Ade- laide, South Australia, Dr. Alcock. Mr. Linton said that the abundant appearance last year of the humming bird hawk moth had afforded many collectors and admirers of nature excellent opportunities of watching this interesting and amusing insect in pursuit of its food, and of observing its remarkable agility, darting from flower to flower, and then poising itself, apparently stationary, while its long proboscis is put out with almost instantaneous velocity. It is very shy, and when disturbed darts away to a great height in the air, but it returns after a time and often to the same spot. He had observed one in his garden, at Old Trafford, about a clump of sweetwilliams, 106 and, after two unsuccessful attempts in one day, he succeeded on the following day in taking it. During the time when the insect was abundant, many letters referring to it appeared in the Times newspaper, and in these it was constantly stated that the insect visits only scarlet or bright-coloured flowers, such as the scarlet geranium and verbena ; but if closely watched it will be found not to confine itself to any particular flower, and in the case just mentioned it chose the sweet williams, though these were at the time quite on the decline, and there was abundance both of geraniums and verbenas in the garden. While staying at Pensarn he observed one of these moths on two successive days resting during the hottest part of the day on a newly whitewashed wall. It might be supposed that the most likely place to find the moth would be hover- ing over the plants on which the larvae feed, which are Galium verum and G. molluga ; but, while in Wales in August, he visited a spot daily, for a fortnight, where these plants were growing in great luxuriance, and never once saw the moth at that place, though he found the larva and suc- ceeded in rearing it. The pupa cannot be said to bury itself in the earth, for it is found with only a few leaves drawn together over it. Mr. Linton also announced having bred the butterfly, Grapta C. album, from the larva taken by himself at Aber- gele. 107 PHYSICAL AND MATHEMATICAL SECTION. February 1st, 1866. E. W. Binney, F.R.S., P'.G.S., President of the Section, in the Chair. The following “ Results of Rain-gauge and Anemometer Observations made at Eccles, near Manchester, during the year 1865,” were communicated by Mr. Thomas Mackereth, F.R.A.S., M.B.M.S.: — During the past year I have been able to register the rain- fall at Eccles, from four different gauges ; two I have placed three feet above the ground, thirty-four feet from any dwelling- house, and fourteen feet from my astronomical observatory, which stands ten feet higher than the receivers of these gauges. This ten feet measures to the apex of the revolving roof of the equatorial room. The receivers of the rain gauges on the ground are of different shapes, one being round, lOin. diameter, the other 5in. square. The other two gauges are placed fouWeet above the ridge of my house, quite above the chimneys and free from the influence of any erections what- ever. One of the gauges is 5in. square, like the 5in. one that is three feet above the ground, on Glaisher’s plan, with an edge inclined inwards, as is usual with rain gauges. The other is also 5in. square, but with an edge inclined .outwards. These gauges are thirty-two feet from the ground. The water falls into glass vessels, into which the receivers are made to fit, exactly like the 5in. gauge three feet from the ground, so that there is no tube required for it to flow through and thus to cause loss by evaporation. Below I 108 present the monthly amounts of rain that fell into each gauge, and the number of miles of horizontal movement of the air. 1865. Rainfall in 5in. square gauge with edge inclined outwards, 32ft. from ground. Rainfall in 5in. square gauge with edge inclined inwards, 32ft. from ground. Rainfall in Sin. square gauge with edge inclined inwards, 3ft. from ground. Rainfall in lOin. round gauge with edge inclined inwards, 3ft. from ground. Amount of horizontal movement of air in miles. January 2238 2-486 2-956 2-952 5,250 February 1-872 2137 2-582 2-489 4,309 March 1-320 1-730 1-700 1-721 4,480 April 0-993 1025 1083 1-102 4,724 May 2-585 2605 2-840 2-884 3,499 June 0-830 0-840 0-943 0-913 3,215 July 1-883 1-992 2043 2-085 3,784 August 4-808 4-832 4-967 4-977 3,615 September 0-481 0-548 0-563 0-571 3,089 October 4-353 4-621 4-491 4-550 4,286 November 2-596 2-830 2744 2818 4,237 December 0-569 0589 0673 0-717 4,263 Totals 24-528 26-235 27-585 27-809 48-751 The next table shows the fall of rain in each gauge under the same general direction of the wind, and the corresponding daily amount of horizontal movement of the air. General direction of the ■wind N. N.E. E. S.E. S. S.W. W. N.W. Average daily horizontal movement of the air in miles 79 124 143 156 178 162 183 149 Fall of rain in inches in 5in. gauge with edge inclined outwards 32ft. from ground 1-414 2-01 1 0259 •1060 5-246 6-738 2099 2-701 In gauge with edge in- clined inwards 32ft. from ground 1-468 2 054 ©3 6 4-285 5-866 7-168 2-280 2840 In 5in. gauge with edge inclined inwards 3ft. 1-472 2-425 0 317 4-550 6000 7-258 2-515 2-949 In ordinary lOin. gauge 3ft. feet from ground.. 1-501 2 415 0-327 4-610 6069 7-363 2-516 3 006 Number of days 6 27 6 35 22 43 15 23 From the above table it appears that the least amount of rain falls with an east wind, and the greatest with a south- 109 westerly wind. The strongest wind with rain is the west wind, and it is known that the strongest gales are from winds a little north of west. This shows, though the above table is framed from the observations of one year only, that the strongest winds are from nearly the same quarter, even when rain falls with them. The following table shows the average daily rainfall in each kind of gauge when the velocity of the wind has ranged between the number of miles indicated in the first column. Daily Movement of Wind. 32 feet from ground. 3 feet from ground. 5in. square gauge with edge inclined outwards. 5in. square gauge with edge inclined inwards. 5in. square gauge with edge inclined inwards. 10in, ordinary round gauge. 0 to 50 miles ■029 •030 •042 •045 50 to 100 •103 •105 •no •114 100 to 150 •220 •232 •231 •233 150 to 200 •108 •118 •122 •124 200 to 250 •151 •160 •174 •175 250 to 300 127 •138 •154 •158 Above 300 •174 •204 •197 •211 The President remarked with reference to the difference between the two elevated gauges that a Glaisher’s gauge, with the rim inclined inwards, would register more than the true amount, as the spray from drops striking the rim on the windward side would be carried over into the gauge ; while, on the other hand, a gauge with a rim inclining out- wards would give less than the true amount, because the spray from drops falling on the rim on the lee side would be blown away and lost. Mr. Baxendell, F.R.A.S., read the following “ Note on the Variable Star S Coronse.” ' This variable was discovered on the 5th of August, 1860, by Dr. Hencke, of Driesen, and a notice of it inserted in the Astronomische Nachrichten, No. 1281. So far, however, as I am aware, no account of any observations made since, has no yet been published, and I have therefore thought it might be desirable to communicate to the Section the results of two series of observations which I have made at Mr. Worthington’s observatory, and which have enabled me to determine its approximate mean period and epoch of maximum. The first series commenced on the 26th of May, and ended on the 31st of October, 1864. A projection of the observations shows that a maximum occurred on the 12th of August, 1864. the magnitude being 6*7. The second series began on the 2nd of April and was continued till the 12th of November, 1865, the star during this time rising from the 1 1 *9 magnitude on April 2nd to a maximum, 6’6 magnitude, on July 17th, and afterwards declining to the 8‘6 magnitude on November 12th. An inspection of the light-curves which accompany this note will show that only one period could have elapsed between the dates of these two maxima ; aud as Dr. Hencke’s obser- vations in 1860 indicate that a maximum occurred about the 1 st of September in that year, we have the following data for the determination of the star’s elements : — OBSERVED INTERVAL NUMBER OF MAXIMA. IN DAYS. PERIODS. 1860. September 1 1441 4 1864. August jj-1 2 339 1 1865. July 17 Equating, and treating by the method of least squares, we have Mean Period = 357-2 days. Epoch of Maximum = 1863, August 10'6. The times of maxima calculated from these elements, compared with the observed times, give the following differ- C-0 days + 2-0 -10-2 + 80 ences : — Ill I have not observed S Coronse when at its minimum brightness, and cannot therefore give the lower limit of its range of variation, nor the interval from minimum to maxi- mum. My observations show, however, that it belongs to the list of variables which increase in brightness more rapidly than they diminish. Thus in 1864 it rose through 4 5 magnitudes in 78 days, but fell through only 1*5 magnitudes in 80 days ; and in 1865 it increased 5*3 magnitudes in 106 days, but diminished only 2 0 magnitudes in 118 days. The place of S Coronse for 1865*0 is 15 h. 15 m. 54"6 s. -j-31°5r2/. The calculated time of its next maximum is 1866, July 17 ; and for the convenience of observers who may be disposed to watch its changes and record their observations, I append to this communication a small chart, and a list of comparison stars with their magnitudes. XV. hours. + 31° 20' -f 31° 40' 4 32° O' 4- 32° 20' 14 m. 16 m. 18 in. £ 4 31° 20' + 31° 40' 4- 32° 0' 4 32° 20' MAGNITUDES OF COMPARISON STARS. a = 6*8 d = 8-6 <7=11-3 6 = 7-9 e = 8-8 A = 11 *9 00 II O /= 10-2 k= 12-6 112 Mr. Baxendell also read the following communication “On the Determination of the Mean Form of the Light-curve of a Variable Star.” Since the publication in the last number of the Society’s Proceedings of my “ Note on T Aquike,” I have been requested to give an explanation of the method I employ to obtain the mean light-curve of a variable star. Many years ago I adopted a method which I afterwards found was very similar to, if not identical with, the one used by Professor Argelander for the same purpose ; but I have recently em- ployed another plan which appears to be decidedly preferable, as it saves time, renders unnecessary a great deal of tedious computation, and gives results of greater weight and value than those obtained by the former method. It is simply this : Having determined the elements of a variable star, calculate the times of all the maxima — or minima, as the case may be — that have occurred during the period over which the observa- tions extend ; then, taking the original light-curve, read off the values of the ordinates for each day, and arrange them in a table having as many columns as there are days in the star’s mean period, or, in many cases, it will be sufficient to take every second, or even third day, always reckoning, of course, from the last preceding maximum or minimum, and then adding together the values in each column, and taking the means, we have the numbers from which to lay down the star’s mean light-curve. 113 Ordinary Meeting, February &0th, 1866. R. Angus Smith, Ph.D., F.R.S., &c., President, in the Chair. Mr. E. W. Binney, F.R.S., said that in the calcareous nodules found in the Upper Foot coal, a mine lying about fifteen yards above the Gannister coal at Moorside and other places near Oldham, he had met with a small stem of fossil wood showing structure in a very perfect state. It evidently belonged to the genus Pinites of Witham, since changed by Endlicher and Brongniart into Dadoxylon ; but after com- paring it with the species figured and described by those authors, and more lately by Professor Schimper of Stras- bourg, he was of opinion that it was a new one. The speci- men was also more complete than any other with which he was acquainted, although it was but of diminutive size. It has generally been supposed that the coniferous woods found in the coal measures were only to be met with in sand- stone rocks, and not in seams of coal or beds of shale, and had been drifted from high and dry lands into the waters in which such deposits had been formed, and had not grown on the places where they were discovered like Sigillaria and its root tStigmaria. The specimen of Dadoxylon now described, however, had equal claim to be supposed to have grown on the spot where it was found as any Sigillaria met with in the same seam of coal. The stem is nearly cylindrical and enveloped in a matrix of limestone, so that we cannot see its external characters. Its diameter is about one half of an inch. On examination of a transverse section of the stem we find a medullary axis composed of irregular polygonal cells full of dark carbonaceous matter separated by intervening spaces Proceedings — I, it. & Phil. Society. — Yol. V. — No. 11 — Session 1865-6. 114 vertically, and thus forming a kind of discoid pith somewhat similar to that noticed by the late Professor Corda, and after- wards by Professor W. C. Williamson, F.R.S., in a paper pub- lished in vol. ix., second series, of the Society’s memoirs. This pith in the present specimen appears to be separated from cer- tain lunette-shaped bundles of hexagonal tubes of large size, arranged in a convex form towards the pith inwards, and lessening in size as they pass outwards into wedge-shaped masses of four-sided subhexagonal cellules arranged in radia- ting series and divided by large medullary rays or bundles which appear to originate in the lunette-shaped masses. On the outside of this internal radiating cylinder are other lunette-shaped bundles similar to those in the inside pre- viously described and also with a convex outside. Then comes a narrow zone of lax tissue which has been a good deal disarranged. Outside this are some thin wedge-shaped bundles of cellules full of dark carbonaceous matter, and arranged in radiating series of varying sizes separated by lax tissue probably representing the bark of the tree. In the longitudinal sections the cellules are seen to be greatly elongated and divided with oblique and transverse dissepiments placed at great distances. Two of the walls, namely those facing the medullary rays, are regularly reti- culated with six, seven, and eight series of hexagonal areolae arranged contiguously but not in a line. In the tangential section the walls of the cellules also show a reticulated appearance something like that previously noticed, but not in so marked and distinct a manner, and the medullary rays or bundles in their section show numerous irregular series of small cellules of one to four, and more rarely much larger cellules. The arrangement of the lunette-shaped bundles next the pith reminds us of similar masses described by Brongniart as occurring in his Sigillaria clegans, but the cellules in my specimen are much more irregular in size than those of 115 Sigillaria, and there are no traces of striae upon their sides. The same may be said of somewhat similar lunette- shaped masses appearing on the outside of the internal radiating cylinder. The areol® on the walls of the cellules are more numerous than in any species of Pinites or Dadoxylon which have hitherto come under my notice, the P. medullaris of Witham having the walls of its elongated cellules reticulated with two, three, and four series of contiguous areolae, and those only on the walls parallel to the medullary rays, while in my specimen they are reticulated with six, seven, and eight, and not only on such walls, but also on the walls at right angles to the medullary rays. The lunette-shaped bundles of cellules both in the inside and outside of the internal radiating cylinder are different from those seen by me in any other specimens of Dadoxylon. For the purpose of distin- guishing it the name D. Oldhamium has been given to it. A paper was read “ On Air from off the Atlantic, and from some London Law Courts,” by R. Angus Smith, Ph.D., F.R.S., &c., President. The specimens of air collected by Mr. Fryer when on his way to West Indies, and those collected in Antigua, are worth remarking, as the first agrees with the figures obtained previously when examining air on the sea shore and open heaths of Scotland, where the highest average was obtained, and the second agrees with the numbers obtained in more inhabited but not closely inhabited places. Those from a law court are interesting ; they are the most deficient in oxygen of any specimens found by me during the day in inhabited places above ground. The first is almost exactly the same as the average found in the currents of galleries in metaliferous mines ; that from the lantern is nearly the same as the specimens found close to the shafts of the same mines, meaning of course the average of many 116 specimens. I have not known any mills or workshops so deficient in air. I consider a room bad when it loses 1,000, and workshops very bad when they lose 2,000 of oxygen out of a million parts ; here the loss is actually 5,000 less than the parks of Loudon. The circumstance is strange, and I hope unusual. A scientific friend happened to call my attention to it and wished me to examine the air. The moisture from the window was collected and there were seve- ral ounces obtained, and more might have been easily found. It was perspiration in great part, the smell of it was distinct. It is putrefying, and decolorises more permanganate now than it did at first. Mere change of air will not purify a room like this — a current must pass through it for a long time until complete oxidation takes place. Oxygen per cent in some Specimens of Air. 18ft. abovo water. Fine day. 2 30 p.m. Lat. 43-05, W. 17-12. 21-0100 21-0000 20-9700 St. John’s, Antigua. April 11th, 1865. 9 a.m. Showery morning. 20-9600 20- 9100 21- 0000 Mean 20-9900* Mean 20 9500 Law Court, Feb. 2nd, 1866. 20-6400 20-6700 Law Court, from the lantern, 4 30 p.m. just as the court was closing. 20-5000 20-4800 Mean 20 6500 Mean 20-4900 * May be rend 209,900 in & million, and so with the others. 117 Ordinary Meeting, March 6th, 1866. R. Angus Smith, Ph.D., F.R.S., &c., President, in the the Chair. Mr. E. Sonstadt communicated the following “ Note on the Purification of Platinum — The tendency of platinum to alloy with other metals, at a temperature far below its fusing point, is sufficiently well known to every user of platinum crucibles. It is equally well known that iron, &c., which has been absorbed by platinum cannot be removed, except superficially, by the action of hydrochloric acid for instance, nor even by heating in acid sulphate of potassium. Stas, in his memoir on the atomic weight of silver, &c., states that he purified his platinum vessels from iron, by causing them to come in contact, at a red heat, with the vapour of chloride of ammonium. The process had to be repeated as often as any yellow sublimate was formed. This process is less effectual, or less conveniently and speedily effectual, than the modifica- tion of it that I have to propose ; because, if the vapour of the sal ammoniac is generated from the solid salt in the vessel to be purified, the heat absorbed in the vaporization of the salt tends to keep the vessel at a temperature below that at which volatile metal chlorides are most readily formed. Instead of chloride ot ammonium, I put dry double chloride of ammonium and magnesium in the platinum vessel intended for purification. The vessel is then heated to about the fusing point of cast iron for about an hour. I find a Gore’s furnace convenient for this purpose. In this process, not Pboceedings— Lit. & Phil. Society.— Foe. V. — No. 12— Session 1865-6. 118 only is chloride of ammonium vapour given off for a long while with the double salt, at a temperature much above that at which chloride of ammonium alone volatilizes, but when that salt is completely expelled, the chloride of magnesium remaining is perpetually being decomposed with evolution of free chlorine, and, frequently, the formation of a crystalline crust of periclase lining the crucible. Platinum thus purified is softer and whiter than ordinary commercial platinum. The method is not available solely for \he removal of iron, but retrieves crucibles that have become dark coloured and brittle from exposure to gas flame, as well as crucibles that have been attacked by silicates during fusion of these with carbonate of sodium. I cannot conclude this note without remarking on the extreme facility with which platinum becomes impure by heating in contact with matters containing only a very small proportion of substance capable of attacking the metal. Thus, a platinum crucible becomes sensibly impure after prolonged ignition at a high temperature, bedded in commercial magnesia. On the other hand, I have kept a platinum crucible at a constant weight, to the tenth of a milligramme, over a series of intense ignitions, when the precaution has been taken to bed it in chemically pure magnesia. A conversation took place on -the cattle plague, in the course of which the President and Mr. Spence stated that the use of carbolic acid as a disinfectant had been quite successful as a preventive in the limited number of cases tried, none of the cattle on the farms where it had been regularly and properly used having yet been attacked by the rinderpest. People rarely used enough. An opinion was strongly expressed by some members that the means which had been adopted to arrest the progress of the disease had, in fact, served to propagate it and extend its ravages, as numerous instances could be cited in which the 119 infection had been carried by the official inspectors from unhealthy to healthy districts, and it was suggested that the inspectors ought to be compelled to cleanse themselves and undergo a disinfecting process before they were allowed to visit and inspect cattle not known for certain to be diseased. It was characterised as a most unwise proceeding to send forth an army of inspectors to invade every farmstead in the kingdom, and not to adopt and enforce stringent regu- lations to prevent the possibility of these men being the means of carrying the dreaded infection into healthy localities. It was remarked that official interference had virtually taken the management of the cattle plague out of the hands of those who, from their practical experience and the deep interest they had in the matter, might be held best qualified to deal with it, and there were grounds for thinking that if the farmers had been left to act for themselves without official interference, as they did some years ago when pleuro-pneumonia carried off large numbers of cattle, the rinderpest might never have assumed its present formidable aspect. A paper was read “ On the Liassic and Oolitic Iron Ores of Yorkshire and the East Midland Counties,” by Messrs. Edward Hull, F.G.S., and William Brockbank. In this paper the authors gave the results of their observa- tions on the nature, geological position, and qualities of the iron ores which are now being worked at intervals from the banks of the Tees to that of the Evenlode in Oxfordshire, extending through the counties of York, Lincoln, Rutland, Leicester, Northampton, Warwick, Oxford, &c. ; at the same time embodying the opinions of previous observers. Remarking that just at the time when some of the older iron-producing districts were giving evidence of approaching exhaustion, the enormous stores of iron ore in the newer form- ations were discovered; the authors commenced by a descrip- tion of the geological position of the strata from which the 1*20 ores are extracted, referring them to the middle lias or marl- stone and the base of the great oolite ; and it was shown that the ores of Cleveland in Yorkshire, Lincolnshire, and Oxford- shire, are derived principally from the lias, while those of Northamptonshire are extracted from the basement beds of the great oolite, called by the government geological sur- veyors “the Northampton sands.” The first district described was that of the East Riding of Yorkshire and the Cleveland hills, which, within the space of about sixteen years, has given birth to the iron trade of the Tees-side, of which Middlesborough may be considered the centre. The ore is here quarried in open and tunnel-works, and brought down by rail from the hills to the furnaces, which are erected along both sides of the river, and which are supplied with fuel from the Durham coal-field. The production of this district in 1865 was stated to be nearly one million of tons of pig-iron annually, drawn from 105 fur- naces in blast. The ores in the valley of the Esk, near Whitby, and those of Guisborough were then described, and particularly the Rosedale ore, which is the richest in the district, and is magnetic. A branch railway is opened to the quarries, which in 1864 yielded nearly 300,000 tons of ore, having a per centage of 35*94 to 49*17 of metallic iron. The iron-stone was then traced to the banks of the Humber, near Hull, by Stokesley, Swainby, Northallerton, Easing- wold, and Market Weighton. The ores of North Lincolnshire were stated to be spread over a wide expanse of country — an area of not less than 100 square miles — having been proved to be quite close to the surface, and their local and geographical position in reference to the sea-ports on the one hand, and the South Yorkshire coal-field, together with the excellent quality of the iron they produced, satisfied the authors that this district was destined to rise in importance as a centre of iron manufacture. The pig-iron from North Lincolnshire is highly tenacious and 121 fusible, and commands a higher price in the market than the Cleveland brands. This superiority appears to arise from the spathic nature of the iron-stone, and from the .presence of manganese in considerable quantities inter- stratified with the ores, and which is mixed in the furnaces. The ore, with its accompanying strata, is very finely shown along the line of railway at Frodingham ; its thickness in different parts of the district varies from twelve to thirty feet. It is being smelted at three works in North Lincoln- shire, and it is also carried largely by rail to the Park Gate Iron Company’s furnaces near Rotherham, and other works in the Yorkshire and Derbyshire coal-fields. From North Lincolnshire the ironstone may be traced southwards along an indented line running parallel to the western margin of the great oolite into Northamptonshire. At the base of the oolite a series of yellowish sands occur — and, in these there are at intervals, beds of iron ore — sometimes extending for miles with considerable regularity, at other times thinning away rapidly. From these beds, the North- amptonshire iron is smelted. The furnaces and quarries are • situated at Gayton and Blisworth, Blakesley, Maidford, and Litchborough, at which place they are more than usually ferruginous. At Duston, where it is extensively worked and smelted, it is more consolidated and is coarsely oolitic. The metal produced is similar to that of the Cleveland district in quality. Large quantities of this ironstone are sent by rail and canal into South Staffordshire, and even South Wales, where it is valued for mixing with the argillaceous carbonates of the coal measures. The Oxfordshire district is as yet almost unopened, but promises one day to be productive of iron on a large scale, similar in character to the Lincolnshire brand. In the neigh- bourhood of Banbury and Chipping Norton, the ore occupies considerable areas — sometimes in the form of tabulated hills, intersected by valleys of no great depth. It occurs here (as 122 already stated) in the middle lias, precisely the same forma- tion as that to which the ores of Cleveland and Lincolnshire belong. The ironstone, however, is generally more calcareous than in the former district, and its richest portions are limited to a tract, of which the village of Bloxham may be considered the centre. As yet the ore has only been worked at Fawler, near Charlbury, and at Steeple Aston, to a very limited extent; but the railways, now in course of construction, will probably have the effect of bringing it within easier reach of the coalfields of South Wales and Staffordshire. The authors remark, in conclusion, that every day’s experience enlarges our acquaintance with the great mineral resources of our country, and that, in the case of coal and iron, it becomes a question which is more largely distributed and likely to outlast the other. MICROSCOPICAL AND NATURAL HISTORY SECTIONS. February 26th, 1866. A. Brothers, F.R.A.S., in the Chair. The following objects were exhibited : — Mounted specimens of twenty-four species of Ostracoda, from Dog’s bay shore-sand, collected by Dr. Alcock, and named by Dr. G. S. Brady. Mounted specimens of many forms of Foraminifera, from a deposit discovered while sinking a well at Boston, Lincolnshire Mr. Sidebotbam. The skull and skin of a male Otter shot in Rostherne Mere, Feb. 16 Mr. Harrison. 123 Dr. Alcock read a paper on Foraminifera from mud washed out from a shell of Halia Priamus in Mr. Darbishire’s collection. He said that part of the interest of these specimens depended on the information they may give as to the nature of the sea-bed where this rare mollusk is found, the exact locality from which it is obtained by the Cadiz fishermen being still doubtful. He exhibited mounted specimens of about forty forms of Foraminifera, twenty-five of them agreeing with British ones as described by Professor Williamson, the others, so far as he knew, not British, and at present unknown to him. He said that the great abundance of Globigerina with fragments of large Orbulinse, appeared to indicate a deep-sea deposit, but the most remarkable feature was the extraordinary profusion of Textularia variabilis, a very considerable proportion of the whole mass consisting of these shells. Bulimina pupoides was perhaps next in abundance, and next to it, in about equal proportions, Cassidulina laevigata, C. obtusa, and Nonionina elegans. Rotalina Beccarii was plentiful but small, as were all the forms of Rotalina which occurred Lagense were scarce and were very small hyaline varieties. Nodosaria radicula was rather common, and three very distinct varieties of it were met with, one of them remarkable for its large size and the raised rings upon its neck. Polymorphina was entirely absent ; and Polystomella, Spiroloculina, and Miliolina were represented by only a very few extremely small individuals. 124 PHYSICAL AND MATHEMATICAL SECTION. Annual Meeting, March 1st, 1866. E. VV. Binney, F.R.S., F.G.S., President of the Section, in the Chair. The following gentlemen were elected officers of the Section for the ensuing year : — E. W. BINNEY, F.R.S., E.G.S. UtCC=lPtTSttfC!rtB. ROBERT WORTHINGTON, E.R.A.S. JOSEPH BAXENDELL, F.R.A.S. treasurer. Me. THOMAS CARRICK. Secretary. G. Y. YERNON, E.R.A.S, M.B.M.S. A paper was read “On the Variable Star R Vulpeculae. « — 20h 58m 22-93. 8= + 23° 17*2'. Ep. 1865-0.” By George Knott, F.R.A.S., communicated by Joseph Bax- endell, F.R.A.S. This star, which is No. 457, hour xx, in the Palermo catalogue, was first recognised as variable, so far as 1 am aware, at the observatory of Bonn. It appears to have been observed with some care by Dr. Winnecke at the Pulkowa observatory, and in a letter to the Rev. R. Main, printed in vol. xxii. of the Monthly Notices of the Royal Astronomical Society, p. 285, that able astronomer assigns the following 125 elements, “ which represent seven maxima observed in the course of three years, with reference to Piazzi’s estimations of magnitude in \ugust, 1803,” viz Period — 138 -6 days. Epoch = 1860, Nov. 6. Having observed this star with more or less regularity during the past four years, it occurred to me that it would not be uninteresting to compare the elements resulting from a discussion of my own observations with those which had been deduced by Dr. Winnecke. The results of this discussion I have now the honour of presenting to the Manchester Literary and Philosophical Society. Projecting my observations in the usual way, I obtain the following dates of maxima and minima, with the correspond- ing magnitudes — Maxima. 1861. Dec. 1 p o CO -8-4 mag. 1862. Oct. 5-0- -7-8 1863. Nov. 19-4- -7'6 1864. Aug. 16-3- -7-5 1865. Jan. 7-3- -7-7 May 25-5- -7-8 Oct. 5-5- -7-5 Minima. 1861. Oct. 26 '3 — 1 3 -6 mag. 1863. Sep. 18-0— 13-2 „ 1864. June 19'5— 13-2 „ Nov. 4-0— 13-1 „ 1865. Aug. 6-3— 12-8 „ Dec. 14-3— 13-7 „ Treating the seven observed maxima according to Mr. Baxendell’s method, we obtain the following elements : — Period = 137'59 days. Epoch - 1864, April 4-95. Comparing the observed times of maximum with those calculated from these elements, and also from those of Dr. Winnecke, we obtain the following differences between calcu- lation and observation : — * The projection of a series of his own observations of this maximum obligingly communicated to me by Mr. Baxendell, yields the following results, in gratifying accordance with my own : — Date of maximum, 1863, jSTov. 18'9, mag. 75. / 126 Knott’s Elements. Calc. — Obs. Days. * 1-41 -2-41 -0-01 + 4-24 -2-23 -2-78 + 1-81 Wtnnecke’s Elements. Calc. — Obs. Days. -3-2 -5-0 + 0-4 + 7-1 + 1-3 + 1-7 + 7-3 the sums of the squares of these numbers being’ 43*75 and 143*78 respectively. But while it thus appears that my own observations accord moderately well with Dr. Winnecke’s elements, it must be confessed that these latter represent more satisfactorily than my own (as indeed might be expected) the magnitude estimates of Piazzi in the years 1807 and 1810, as given by Dr. YVinnecke in No. 1224 of the Astronomisclie Nachrichten. At the same time it must be remembered that my own elements were deduced solely from my own observa- tions, without reference to any of earlier date. Treating the six observed minima in the same manner, we obtain the following elements, the period presenting a striking accordance with that deduced from the observed maxima : — Period = 137-55 days. Epoch =1864, June 17 ’50. The differences between the calculated and observed times of minima being : — Calc. — Obs. Days. + 2*35 - 1*60 - 2-00 -1-95 - 2-15 + 5*40 127 An examination ot the mean light-curve (a copy of which accompanies this communication) which was laid down from the co-ordinates resulting- from a discussion of all the observa- tions I have obtained, yields the following results : — Mean magnitude at maximum 777 Mean magnitude at minimum 13-14 Mean range of variation 5-37 magnitudes. Mean magnitude 10-32 Interval from minimum to maximum 66 -0 days. Interval from maximum to minimum 7 1 *6 days. Interval from min. to mean mag 25 -8 days. Interval from mean mag. to max 40 -2 days. Internal from max. to mean mag. ..* 37 -3 days. Interval from mean mag. to min 34-3 days. Interval from mean niag. before to mean mag. after maximum 7 7 -5 days. Interval from mean mag. before to mean mag. after minimum 59 -1 days. Ati examination of the various results of observation and calculation given in the former part of this paper suggests the following general remarks. Like many other variable stars R Vulpeculm increases more rapidly than it decreases. The intervals between successive maxima and minima are subject to some little irregularity. And the observed magnitudes at maximum and minimum vary to the extent of some nine tenths of a magnitude. Still, as compared with some other stars, the movements of this variable most be regarded as tolerably regular. Although by no means so highly coloured as some variables, I have frequently noted the star in my observation book as “ruddy,” or “decidedly ruddy.” The maxima observable during the present year will fall, according to my own elements, on the following days: — July 17*0 and . December 2-6. The observable minima will occur on May 6*3 and September 20 8. 128 The stars which I have used for comparison with R Vulpe- culse are shown in the small chart which accompanies this paper, and their magnitudes are as follow, the numbers in the cases of > lh. „ Secondary ,, „ 1th. a.m. 3h. a.m. Owing to the shortness of the period over which Mr. Bates’ observations extend, it is probable that the results derived from them may be open to considerable correction, when a more extended series becomes available. I find, however, that when this short series is divided into tu o or even three groups, the main features of the daily variation are still preserved in the results of each group, and I do not, therefore, anticipate that any corrections which may hereafter be found to be necessary, will be of such a character as to affect materially the probability of a close connection between the daily variations of rainfall, and the diurnal oscillations of the magnetic needle, and I hope to be able in a future communication to bring forward other facts and results bearing upon this interesting and important question. Whatever views may be taken as to the cause of the unequal distribution of the rainfall in the different hours of the day, it could, at all events, hardly have been expected that the .greatest amount of rain would fall at that period of the day when the rate of increase of the difference between the tem- perature of the dew point and that of the air, is greatest ; and /?.£- 134 when, therefore, according to generally received meteorological principles, there would appear to be little probability of a con- densation of vapour into the form of rain. I cannot conclude this communication without gratefully acknowledging the kindness of Mr. Bates, in affording me an opportunity of examining his valuable observations which form, I believe, the only series of the kind ever yet made. PHOTOGRAPHICAL SECTION. February 8th, 186(3. Dr. J. P. Joule, F. R.S., Vice-President of the Section, in the Chair. Mr. Sidebotham brought before the section a number of pictures, by Boulton and Watt, which had been supposed to be photographs. The examination he had made of them convinced him that they had been produced by a different process. Mr. Dancer coincided in this opinion. He thought that the camera had been employed, but solely for the purpose of enabling the artist to trace the outline, and to enlarge or reduce the image to any required scale. The shading would be an after process, the crayon employed being made of some resinous or fatty substance mixed with the colour. March 8th, 1866. Dr. J. P. Joule, F. R.S., Vice-President of the Section, in (he Chair. Mr. Brothers, F. R. A. S., stated that since the last meeting he had tried the use of wax dissolved in ether, as recommended 135 by Mr. Rogerson, for the purpose of cleaning glass plates, and was quite satisfied it was an excellent method of cleaning glass. A paper was read “On the Pantascopic Camera,” by J. R. Johnson, Esq. Communicated by E. C. Buxton, Esq. But a few years had elapsed since the introduction of the Daguerreotype, and photography had not yet passed beyond what may be termed “The Daguerreotypic Era,” when the unsatisfactory nature of the “ bits” of landscape produced by the lenses then in use became fully recognized. What could be more annoying to an artist desirous of producing pictures of some of the splendid architectural monuments of Paris than to find that from no possible point of view could the whole of many of the finest of these be embraced ? The desirability of not only effecting this, but of repro- ducing as pictures some of those striking “ coups d’ceil” which abound on the banks of the Seine, struck an eminent artist-engraver, Mr. Martens, so forcibly that he immediately set about finding a remedy, and he was not long before he had attained his object. He found that if a lens be moved horizontally upon a pivot placed beneath its optical centre, the image is stationary notwithstanding the motion of the lens. Now as all subsequent rotating cameras are based upon this principle it is desirable that we should clearly understand it, and the instrument I am about to describe, and which is intended to be used for viewing panoramically views produced by a rotating camera, will enable us to do so. Fig. 1. 136 In fig. 1 we have a lens mounted in a socket so as to turn horizontally, and behind it we have a piece of cardboard bent to form part of a cylinder, of which the focal length of the lens is the radius. Now, if in front of this we place a taper, an image of the taper is formed upon the cardboard screen. We may turn the lens backwards and forwards through a short arc, and yet you will see the image remains stationary. If we move the taper sideways keeping it at the same distance from the lens and turn the lens towards it, an image is produced on a different part of the screen. If a sufficient number of candles had been placed before the instrument and we had limited the action of the lens upon the screen to a narrow vertical band of light, the screen would have received consecutively the images of all the candles laid side by side, and perfectly distinct from each other. Now if for the cardboard we substitute a bent Daguerreotype plate, and if for the ordinary reading glass we put a good photographic lens, and for the series of tapers any landscapes or series of lighted objects, we shall have an exact reproduction of Martens’ camera. He took a number of beautiful views of Paris, from the bridges of the Seine, but the instrument failed in other hands than his. The difficulty of polishing and preparing large silver plates was of itself a serious obstacle, and a still greater want of success arose from the fact that Mr. Martens not being familiar with the practice of mechanics, did not attempt, or failed to produce the motion of the lens by self-acting means, and it requires the greatest skill and care to maintain a uniform motion for the length of time necessary for due exposure by means of the hand alone. Even in the hands of Mr. Mayall, so successful in large Daguerreotype plates, and so careful and intelligent an operator, the instrument failed completely. He worked for a long time at Niagara, unsuccessfully, before obtaining the few views he brought away with him. 137 After the Daguerreotype give place to albumen and col- lodion on glass, Martens’ camera was laid aside, but in 1854 he and a nephew made an effort to replace the bent plate at the back of the camera by a flat plate ; and he contrived an apparatus for giving such a motion to the plate and lens respectively, that he succeeded in getting pictures upon such a plate more or less successfully. To show what these motions are, we will go back to the instrument which has served to illustrate Martens’ first camera. We will remove the bent cardboard, and making it straight, we will place it against the circular edge which pre- viously held it bent. If the taper be placed directly opposite the centre of the instrument, the flat paper must be at right angles to the ray of light, at a tangent to the curve on which the circular plate was bent, and the centre of the plate must be opposite the taper. Fig. 2. If the light be shifted to b fig. 3 the lens must be turned, and the plate must also be turned so that it is still at right- angles to the ray, and tangential to the curve as before, but the image must be received away from the centre. This will bring us to the position fig. 3 and if the one taper be moved in the opposite direction the lens and plate will be as shown in fig. 4. Fig. 3. 138 Fig. 4. If the rotation of the lens and the change of position of the plate he made with due regularity perfect definition is obtained, but the greatest accuracy is necessary to obtain this. To return to the history of this instrument. Mr. Martens by a note to the Academy registered the fact of having pro- duced views in this manner, and his instrument was laid aside until it was disinterred for the first time we believe last sum- mer. As far as we are informed, although Mr. Martens has yearly produced splendid views of Swiss scenery and has regularly published them, yet no product of the machine has been shown by him since 1854, the elaborately engraved panoramas of the Swiss alps having been produced by laying views taken by the ordinary camera side by side, and copying them juxtaposed. Various other gentlemen subsequently undertook to solve the problem. Among others may be mentioned M. Garella, an engineer officer employed in Algeria; Mr. Sutton, so well known for his high attainments and inventive talent; Mr. Hosmer, &c. The plans of these gentlemen have been published. Other plans have been heard of, as those of Mr. Rawlinson, of Kes- wick; Mr. Stuart, an Indian officer — but those plans have not been made known. It would be an interesting subject to examine all these projects in detail, but to understand them would require numerous diagrams and perhaps models. In general terms it may be stated that all of those known, including that of Martens, possessed two features which render 139 them quite distinct from the instrument we are about to describe, and which will, we believe, serve to account for the fact of these projects remaining as such, or never at least pass- ing from the first to a more perfect stage of development. These features are, 1. The instrument was placed upon a large table upon which the pivot was fixed and upon which the plateholders rolled, the motion of the supporting rollers describing com- plicated curves upon the table, which curves Mr. Sutton recognised as being evolutes of the circle of rotation. 2. No direct mechanical means were employed for effecting the relative motion of the plate and lens, guide curves formed by trial or less efficient means being alone used. 1 believe I may state without fear of contradiction that up to the year 1862 no views produced by any of the inventions alluded to had been publicl) shown, nor views by any similar instrument purporting to produce pictures on true panoramic projection by continuous motion. Several tolerably success- ful attempts had been made to place two or more views side by side upon the same plate by means of a shifting back. But these compound pictures are merely views in plane per- spective placed side by side upon the sides of a polygonal prism, and have no pretensions to be considered views in panoramic or any other correct projection. It was not until the year 1862 that I succeeded in taking panoramic views with any degree of success. I had been employed in devising plans for effecting this object since 1860, aided by a working mechanic, Mr. Harrison. After passing over the same ground as some of the gentle- men above referred to without being aware of their labours, I succeeded in 1862 in perceiving that the complicated motion of the plate and lens might be really resolved into two simple rtiovements, a circular motion of the whole apparatus, and a rectilinear motion of the plate ; and that if the motion of the 140 camera revolving be made to carry with it a strait rail at the back, the plateholder has only to traverse this in a right line to give the due motion required. By forming a groove upon the edge of the circular base plate upon which the camera rotates, and turning this to the proper depth, the due rectilinear motion of the plate behind the lens may be given by means of two strings or wires, one end of each of which is attached to the disc or base plate and the other to the carriage containing the plateholder, so that if we remove the clockwork by releasing the spring which holds it up to the inner edge of the circular base, we can obtain all the necessary motions for working the camera with- out either wheel or pinion or any mechanism whatever unless the wires and disc and the five friction rollers upon which the apparatus moves can be called such. Views may be taken with the instrument in this state, but the accuracy necessary to produce an equal tint, particularly in the skies, is unattain- able except by clockwork. The latter is extremely simple. It is a small clock movement moved by a spring, chain, and fusee, and is regulated by a fly or series of flys, the blades of which may be set at any angle from the horizontal to the vertical. It drives the instrument by means of a small steel pulley gearing into the milled edge of the circular base by a process which may be called a compromise between frictional and toothed gearing, and which has advantages that neither of these possesses singly. In my rude attempts to illustrate the principle of the rotating camera I said that the ray of light passing through the lens must be limited. The reason of this is obvious. The true surface for receiving the image is a cylinder, but that substi- tuted in the flat plate camera is a plane surface. Now, the smaller the angular aperture of the narrow strip of light employed, the nearer the tangent approaches the curve. 141 There is great discrepancy between the curve and straight line, when the width of the strip is equal to a d, fig. 5, but the difference is inappreciable when limited to b c. The width of the active rays thus employed, is determined by a diaphragm, with shifting sides, placed at the back of the camera, near the surface of the plate, and advantage has been taken of this in order to produce clouds, and generally atmos- pheric effects not attainable in the ordinary camera. By making the aperture taper thus Fig. 6. I T or | 1 Liu J‘ ■U the narrow portion being opposite the sky, it is obvious that a totally different exposure will be given according to the width of the opening, and directly proportionate to the extent of that opening. If the part (a) be fifty times the width of the part ( b), then the time of the exposure of the first plane of the picture and that portion of the sky which approaches the zenith will be as 50 to 1. Now we know that we can get the most delicate cloud by a sufficiently short exposure, and that we can also get parts n e in deep shadow by an exposure sufficiently long, but hitherto we have not been able to obtain these simultaneously. Several hundred views upon the table will show to what extent of perfection this principle of unequal exposure has been carried. As all of these views were obtained during last season, many of them at elevations of from eight to ten thousand feet above the sea ; and as the parts of the larger instruments had to be detached and carried separately and then mounted together on arrival at the elevated station, it may be safely alleged, we think, that the pantascopic camera is efficient in producing what it professes to do, and that it is a practical instrument bearing the necessary amount of rough usage inseparable from a campaign like that undertaken by the photographer who produced these views. Having already occupied so large a portion of your time, I will only add a few words as to the nature of the perspective in which these views are produced. It is a very common error to suppose that there is only one sort of perspective, and I was surprised to see that when the pantascopic camera was first explained to the Photographic Society of London, the vulgar view was entertained by at least two members of the council of that learned body. On that occasion, two gentlemen entered their protest against the assumption that the views shown or taken by the camera were true. The inventor very pertinently asked, What is truth — what is your standard ? Do you mean that the views are not in plane perspective? But I have already said they are panoramic views. How can they be in plane perspective if they are panoramas ? It was evident that to them there was but one perspective ; but it has been said by competent authority that there are as many kinds of perspective, as there are imaginable surfaces upon which to receive the visual rays passing from objects to the observer. At least three such 143 systems of perspective are acknowledged and acted upon by artists. We may call these spherical , cylindrical , and plane perspective. A painting upon the interior of a spherical dome, or a view taken by Sutton’s beautiful spherical lens, is an illustration of the first system ; Burford’s or Selon’s views on the walls of a circular apartment, or the pantascopic views, illustrate the second system ; and an ordinary perspective drawing, or a view taken with a triplet or new doublet lens, furnishes us with an illustration of the third system, or that which is usually employed by artists. Now all these are really true, but to be absolutely so, the pictures must be viewed upon surfaces similar to those upon which they have been projected, and from the same station point. Mr. Sutton’s pictures must be taken and viewed upon bowls of glass, the eye being in the position of the lens when the view was taken. With Burford’s panorama we must place ourselves in the centre of the room and turn round so as to view the picture as we should view the landscape it represents. This is equally true of a picture in plane perspective, so that if we really insist upon absolute truth in viewing a picture taken by a lens of four-inch focus, the picture must be brought within that distance from the eye, or the extreme lateral objects will not fall upon the retina at that angle which they would do in viewing the landscape itself. As our object is usually to produce pleasing pictures, rather than an absolutely truthful representation of the scene, the discrepancy between the pantascopic pictures viewed flat is rarely objectionable, indeed, if we examine the numerous views before us, we shall see that in many of them the widening of the base line is advantageous, and often adds to the value of the picture, by giving better arrangement or composition. Perfect truth may at all times be obtained by 144 curving- the picture, or by mounting it in an instrument I have devised for the purpose, and which I propose to call a Pantascope or Orthoscope. In that instrument the curved picture and lens have a definite relation to the lens and camera employed, so that the images are seen exactly in situ, and if for the lens we substituted a theodilite or similar instrument, the horizontal bearings of each object could be taken as in nature. As only a narrow strip of the field is employed, the view is free from the distortion which we should have had with the same lens covering a large field. It will be seen, on examining pictures in this instrument, that from the fact of the lens being thus truly placed we have on looking through it such admirable light and shade, and such perfect modelling of the objects, that the effect is artistic relief in the highest degree, almost in fact competing with the solidity due to binocular vision. As the lens magnifies the objects considerably, beautiful detail is obtained, the geologi- cal character of the distant rocks and the peculiar character of the ice of the glaciers being represented with most striking effect. These views have been shown to the Alpine Club and to Professor Forbes of Edinburgh, whose labours on the glaciers are so well known. All concur in considering them the most perfect representations of the subject which have been yet produced. Mr. Buxton said that he could add his testimony as to the amount of rough usage which a Pantascopic Camera would bear without Jbeing rendered unfit for work. The camera he had used last summer was terribly knocked about on its way from London, and afterwards in Scotland, but the machinery always worked as smoothly as he could desire. 145 Ordinary Meeting, March 20th, 1866. E. Schunck, Ph.D., F.R.S., Vice-President, in the Chair. Mr. John Patterson was elected an Ordinary Member of the Society. Dr. J. P. Joule, F.R.S., exhibited a balance which he had constructed on the principle which had been introduced by Professor Thomson, and employed by him in weighings for a long time. The adjoining figure will fully explain the instrument. The beam has a leaden weight let into its extremity b. It is supported by a wire a a stretched between the sides of the box containing the balance. This wire is led round so as to form the suspender a a of the scale. Silk threads c c, c c, hanging from the cross pieces, form a gimbal system by which the scale is supported in such a manner that any variation in the position of the weights does not alter the torsion of the suspender. A counterpoise of known weight is placed on the stage d. When an article is to be weighed it is placed in the lower part of the scale s, and then, the counterpoise being removed, weights are placed on the stage to effect the counterpoise in the new condition. The difference between the first and second counterpoises of course gives the weight required. The upper edge of the beam is furnished with an index for showing minute effects ; and attached to this is a small bottle e for holding shot or sand, by the addition of which the stability of the beam may be decreased to any required extent. The instrument exhi- • bited was able to weigh articles of upwards of 3,000 grains to one hundredth of a grain. Dr. Joule stated that he had also employed Professor Thomson’s principle in the construc- Pkoceedings— Lit. & Phil. Society.— Vol. V.— No. 13— Session 1865-6. 146 tion of a galvanometer for the absolute measure of electrical currents. In this instrument a flat coil is suspended between two fixed flat coils, one of which attracts while the other repels the suspended coil, to which last the current is con- ducted by means of the suspending copper wires. This electrical balance is sensitive to one part in two millions. 147 Mr. Binney, F.R.S., exhibited a singular mineral which Mr. Ward of Longton had found in a nodule of clay iron- stone from the North Staffordshire coalfield. At first sight it looked like a fossil coral of the genus Cyathopliyllum, but on more careful examination it appears to be a mineral mass in a semicrystalline state. The form of the mineral appears to have been spheroidal with crystals radiating from the centre. By the kindness of Dr. Crace Calvert he had ascer- tained the specimen to consist chiefly of carbonate of lime, carbonate of iron, and phosphate of lime, with traces of magnesia, alumina, and organic matter, and ten *per cent of silica. He also exhibited a beautiful white specimen of carbonate of strontia obtained from a vein of carbonate of lime. It occurred among the lime in radiated masses similar to those of carbonate of barytes as sometimes found in veins of sulphate of barytes. This mineral has been found in con- siderable abundance, but up to this time it is believed that no use has been found for it on a large scale. Messrs. Hull and Brockbank exhibited specimens of the iron ores referred to in their paper “ On the Liassic and Oolitic Iron Ores of Yorkshire and the East Midland Coun- ties,” read at the last meeting of the Society. Professor Roscoe stated that he had just received a letter from Professor Bunsen, announcing the discovery of a most interesting and important fact, namely, that the well known black absorption lines of the Didymium spectrum, when examined with polarised light, vary according to the direc- tion in which the light is allowed to pass through the crystal. This shows that the position of the black absorption lines is in some degree dependent upon the physical structure of the body through which the light passes, and is not merely determined by its chemical constitution. 148 A paper was read entitled “ Notes on Cotton Spinning Machinery. Part II. — Roving Frames.” By J. C. Dyer, Esq., Vice-President. Having in Part I. of these Notes given an account of the inventions and improvements that had been applied to the mule jenny, and for converting it into the self-acting mule, the present paper in like manner traces the origin and pro- gress of the machines known as roving frames, which come next in the order of scientific interest, as having engaged the labours of many eminent mechanics, through a long course of years, to bring them into their present accurate form of working. The rovings are equalised by doubling and draw- ing before coming to the roving frame, in which they are again drawn and slightly twisted to fit them for spinning ; but the twist is not enough to give them strength to be taken up by the drag of the bobbin, as is the case in throstle spinning, so that the bobbins must he driven separately from the fliers and their speed must vary according to their dif- ferent diameters, so as to make the surface motion of winding on to correspond with that of the delivering rollers, and when the latter motion is changed the former must he made to agree with such change, which is called the differential motion ; and to make these agree with the frequent changes required was attended with much trouble and difficulty in working, which ultimately led to the introduction of the machine called the “ tube roving frame,” in which the said differential motion was wholly dispensed with. In this frame the bobbins are mounted on cylinders and turned by the friction of their surfaces. Being geared with the deliver- ing rollers, their motions were thus made to agree at all speeds. But another property of importance in the tube frame was the twisting and untwisting of the rovings and the pressing of them hard upon the surface of the bobbins, so that the surface motion could be made accurate. This tube frame to a large extent was substituted for the bobbin and fly frame for 149 low numbers, but it could not.be made applicable to rovings for fine spinning ; but the pressing of the rovings hard upon the bobbins in the tube frame rendered the application of the presser to the fly frame of great importance. After many experiments this object was effected, and the application of the presser to the bobbin and fly frame was carried into effect by means of springs, or the centrifugal action of revolving weights attached to the arms of the fliers, and both of these methods were set forth in the patent for those improvements. Nevertheless several competing parties afterwards obtained patents for very trivial changes, called “ inventions,” for applying the said spring and centrifugal actions to press the rovings upon bobbins. The differential motion of the bobbin and fly frame con- tinued very imperfect until Mr. Henry Houlds worth’s import- ant invention of a self-adjusting apparatus for giving the differential motions required. This discovery of a very simple train of movements for securing the required rotations of the delivering rollers of the bobbins and of the fliers will at once be recognised as an invention of a high order in mechanical science. From the limits of this abstract the main features only of these delicate movements can be given, and for the details the paper must be consulted in extenso. I may here add that about sixty years ago Mr. John Kennedy employed rotating tin cans for giving- twist to rovings ; but as they could not be driven with suffi- cient speed, the old throstle spindle, enlarged to suit rovings, was adopted for the frames called the “ slubber” and the “ bobbin and fly,” and these frames, with many improve- ments by the same gentleman and others, were in extensive use until partially superseded in the year 1828 by the tube frame as before mentioned; and the suggestive nature of new inventions and discoveries as leading to the production of others is strikingly shown in the successive applicationof those in the tube frame to the bobbin and fly, as before said. 150 Again, Mr. Houldsworth’s beautiful differential motion, then called “ Jack in the box,” being governed by bands and pulleys, their chance of slippage rendered it desirable to sub- stitute toothed wheels, on which occasion Mr. John Kennedy and Mr. Peter Ewart each discovered the three-wheel motions since adopted — those of Mr. Ewart were mitre wheels, Mr. Kennedy’s, spur gearing — the latter being mostly preferred. And it is worthy of note that the three mitre wheels for giving the differential motion in the slide lathe, required for turning cones, had been long in use and publicly seen with- out any one having dreamed of the application of them to other objects ; nor was Mr. Houldsworth at all aware of these slide lathe differentials until pointed out to him by Mr. Ewart. The paper concludes by an earnest appeal to Mr. Houlds- worth and other eminent mechanicians personally connected with the progress of modern inventions and improvements of the machinery employed in our manufacturing establish- ments, to record their own experience and observations upon the several branches with which they have been more espe- cially conversant, as has been done by Dr. Fairbairn in his published works, and as the author of these Notes has aimed to do. The following papers were read at the Photographical Section Meeting, February 8th, I860. “On the Supposed Photographs by Boulton and Watt.” By JosErH Sideuotham, Esq. About three years ago the scientific world was startled by the announcement of the discovery of sun pictures, on paper and on silver plates, said to have been produced at the close 151 of the last century, by Matthew Boulton and James Watt ; shortly afterwards, Mr. Smith, of the Patent Museum, read a paper on the subject, and exhibited the pictures in question at a meeting of the London Photographic Society, and also produced copies of many documents connected with the subject. The whole was published in the Journal of the Photographic Society , together with the discussions, and a large amount of correspondence appeared in the journals. No conclusion, however, appeared to be arrived at, nor any suggestions made of the process by which the pictures on paper could have been produced. During the last winter, in company with Mr. James Nas- myth, I paid a visit to the Patent Museum. Through the kindness of Mr. Smith, we had an opportunity of examining these pictures carefully, hearing what he had to say on the subject, and seeing some of the original letters and papers. Mr. Smith also gave me a small portion from one of the torn pictures, and has since sent me another, for the purpose of careful examination. Through his kindness, also, I am enabled to exhibit to you this evening a number of the per- fect pictures, in the hope that, by your seeing and examining them, some light may be thrown on the secret of their production. It will be, perhaps, well to give you a short historical sketch of the pictures. Those who wish to refer at length to the published accounts, will find them in vol. viii. of the Journal of the Photographic Society. The pictures in question consist of a number on paper — some large (so large, indeed, that it requires two sheets to form one subject), others small. They vary in shade of colour from black to dull red — many being of a sepia tone. Some are plain, others coloured. These pictures came from ■ Boulton’s old house at Soho, and many of them are evidently experiments, being marked with large figures in pencil. The plates are two silvered copperplates, also found in the 152 old library at Soho. These we will, however, leave for the present, and proceed with the pictures on paper. According to the evidence of letters and other documents produced hy Mr. Smith, Matthew Boulton was in possession of a secret plan for producing what he called “ mechanical pictures ” — the inventor, or partial inventor, of the process being a person of the name of Eginton, who appeared to superintend this department of the Soho establishment. These pictures (all apparently copies of paintings) were pro- duced rapidly, and at very low prices — from seven shillings and sixpence upwards, according to the size. They appear to have all the touches of a painting. Sometimes they were transferred to canvas and painted in oil colours, sometimes tinted on the paper itself, sometimes transferred to copper plates. Orders appear to have been given to artists for the sole purpose of having the paintings to copy or reproduce. They were sold in considerable numbers, and could, it appears, be produced of various sizes according to order. The pictures on paper were all reversed, the figures left- handed. When more than one sheet of paper was required for a subject, the picture was not joined in a straight line, but curved, so that the junction fell in the shadow, as in the leadiug of painted windows. Eginton was a glass painter, and perhaps took his idea from that source. There is much interesting matter published concerning a proposed government pension to Eginton, and a letter to the Earl of Dartmouth on the subject from Matthew Boulton ; also letters from Mr. M. P. W. Boulton and others ; but, as they have no dii'ect bearing on the mode of producing the pictures, I merely allude to them here. Although it is well known that Watt, Boulton, Davy, Wedgwood, and other members of the Lunar Society ex- perimented in photography, and tried to fix the images formed in the camera, we have the direct statement that, up to the year 1802, Wedgwood had been unsuccessful — that no 153 amount of exposure appeared to produce an image. It is not likely , therefore, that, for years before (the mechanical production of pictures was in full operation in 1790), his intimate friend Matthew Boulton should not only have been in possession of a secret mode of fixing images of pictures but actually producing and selling large numbers of them. For this and other reasons we must, I think, decide that these pictures could not in any way have been produced in the camera; besides the great size and the perfect definition would be beyond the power of any instruments that could then be made. There is another argument, too — that if the camera could have been used, paintings would have not been the only subjects reproduced — views from nature, or, at any rate, works of art, would have been experimented upon. On some of the pictures are seen curious small spots, each casting a shadow in the same direction — a very familiar appearance to those who have copied oil paintings in a raking light, when each raised spot of colour does actually cast its shadow. This has been considered an evidence of the pic- tures having been produced by the camera; but I shall further on be able to account for this appearance in another way. Although we cannot call these pictures photographs, seeing that they have been produced by some different process from any we are acquainted Avith, we have the distinct evidence of Dr. Lee and Mr. Hodgson, clear and unmistakeable, that pictures produced by this mechanical process were pointed out by Matthew Boulton as having been produced in some way by sunlight. Perhaps Ave shall do Avell to narroAv the field of inquiry, by considering some of the suggestions that have been made, and shoAving Iioav they could not have been produced. We may decide that they could not be copies by hand: — 1st. Because they are distinctly called ££ mechanical pictures,” produced by a secret process. 2nd. Because in two copies of 154 the same subject such minute lines and marks are found to exist in both — lines not visible without the microscope, quite impossible to be copied by hand. Besides, Ave have the tes- timony of those whose lives have been spent in engraving and making facsimile productions that the thing is impossible. They could not, I think, be impressions from metal or blocks. The peculiar surface of the paper, and the colouring matters used, Avould be quite unsuited to printing purposes. The great cost of engraving these large surfaces for but a limited number of copies ; the different sizes in which the pictures could be made; the non-necessity, in such case, for the reversing of the pictures — are all good arguments against any system of engraving being used. It has been said that the plate mark on some of the pic- tures suggests the employment of plate printing; but, on examination, as you will see, the supposed plate mark is merely an embossed line on the paper, either intended as a finish or, more probably, to mislead as to the mode of production. The specimens for your examination consist — 1st. Of two similar pictures — one plain, the other coloured. A careful examination of these will show that spots and lines only visible Avith a lens exist exactly the same in each, such as no artist could possibly copy ; yet, strange to say, there are considerable differences — some of them striking; but these are of precisely the same nature as you would have in an under-exposed and an over-exposed print, both from the same negative. 2nd. We have a coloured mechanical picture — subject, The Graces Awakening Cupid. This may be compared with an engraving of the same subject, evidently both taken from the original painting. In this you will notice the mechanical picture is reversed. 3rd. We have a red mechanical picture — Flora Bedecking Pan. This may also be compared Avith an engraving of the 155 same subject, or rather one somewhat similar. In the en- graving another figure is added ; and there are other dif- ferences. In this case the original picture had probably been reproduced with additions, and the engraving taken from the later one. 4th. A large picture in two parts, from a painting by Benjamin West. You will notice, as peculiar, the mode in which the two portions of the picture are intended to be joined together ; also that the two halves are not of the same tint, either in shade of colour or depth. I will now give you the result of my examination of the pictures and the fragments given to me by Mr. Smith for the purpose of analysis. The surface of the paper appears, first, to have been prepared with gum and sugar. On that is the image impressed, consisting of finely divided particles, apparently laid on either in the form of vapour or very fine powder. Over the picture is a coating of albumen. This has been applied, most likely, by floating the picture on the surface of a vessel containing albumen. The picture has then, probably, been taken up carefully and allowed to drain for a short time, and then laid flat to dry. Small air bub- bles, or particles of dust, on the surface would just produce the curious appearance of projections and shadows before- mentioned — the powdery surface being slightly carried away and deposited, just as we see it. Those who have made experiments in photography — such as in the old carbon pro- cess, &c. — will at once fully understand my remarks. The albumen, in drying, has run into the hollows of the paper, as we see in the specimens. It is easy now to see how the images could be transferred to canvass, or painted upon on the paper. How the images were formed I cannot even venture a suggestion. The process, if re-discovered, would be still valuable, even with our other and various modes of reproduc- tion. For effect and beauty the specimens now shown are 156 not to be despised ; and, for permanency, have had the test of nearly eighty years. Many of these pictures must he in existence in old houses and country inns ; and, if more specimens were obtained, some clue to the secret might he found. I feel confident 1 have more than once seen specimens. Once, in particular, when on a photographic trip, in 1853, with our old member, Mr. Barton, either at Ludlow or Hereford, we saw several of them, and puzzled ourselves to make out what they were, with their striking photographic appearance. At length we decided that they must he sepia drawings. The pictures on silver plates are two, and, on certain evidence, thought to be views of Soho House before the alteration. As this took place at the end of last century, these pictures, according to that idea, must have been taken at least sixty-six years ago. All we have to judge upon is this evidence, which is rather weak. The pictures are evidently taken in the camera, and arc genuine photographs. From the evidence published in a pamphlet by Mr. M. P. W. Boulton, it appears highly probable that these pictures were taken about twenty-eight to thirty years ago by his aunt. Miss Wilkinson. Independently, however, of this, 1 fear we must give them up as modern productions. Their appearance is that of daguerreotypes of the early period, made sensitive with iodine alone ; and the image, as may be seen through the micros- cope, is composed of mercury vapour. But another piece of evidence appears to me more conclusive still, and that is the size of the plates. I have here a daguerreotype view of Rome, taken in the early days of the art — one of a number taken at that time in Rome and Paris. If we now compare the size of the plate with the Soho pictures, we shall find them identical. Such could scarcely be an accidental coinci- dence. These plates were not made or used for any other purpose ; and it is not within the bounds of probability that 157 the standard size of pictures, taken by Daguerre in 1835, should have been precisely the same as those used by James Watt in 1799. However, from the stamp on the corner of my plate, the peculiar form of the figure four (4) points it out as a French production ; whilst the Soho plates are apparently English, rendering the possibility of their exact coincidence in size still more improbable. “ Speculations on the Process employed by Messrs. Boulton and Watt in the Production of the Pictures called by them ‘Mechanical Pictures.’” By J. B. Dancer, F.R.A.S. My remarks at present are confined to the two pictures on the table, of human figures, numbered 7 and 8. They measure 17xl3| inches, and are identical in size and sub- ject. By the kindness of Mr. Sidebotham I have had an opportunity of making a minute examination of them. The only apparent difference between them is, that No. 7 is in plain ink, and in No. 8 the garments of the figures are coloured — one red and the other blue. I am informed that these pictures are similar to those which were supplied by the firm of Boulton and Watt, and copies from originals sent to them. They were issued, it is said, with tolerable rapidity, and at a very moderate price ; but the process by which they were multiplied was kept a profound secret. At the first glance the pictures look as if they. were pro- duced by hand ; but, on comparing them carefully, the close resemblance in the drawing in each is found to be so remark- able that no artist, however clever, could produce such exact duplicates without great expenditure of time. A more minute examination by means of a lens shows scratches and lines (evidently accidental) which correspond accurately in each picture, affording a convincing proof that these copies could only be produced by some mechanical or chemical agency. 158 It has been stated on good authority, I believe, that a darkened room or tent was used, also that the presence of sunlight was required in the process. Now this at once sug- gests the use of the camera obscura — an instrument which was perfectly well known at that period. A common method of exhibiting this instrument was to darken a room and fix a lens in a hole made in the window-shutter, and view the images produced on a screen of paper placed opposite to the lens. By this method a reversed and inverted picture would be seen by the spectator. Another form of camera in use at that time consisted of an upright box with a sliding tube through the top, in which was fixed a lens, and above this a mirror placed at the angle of 45°. This form is still in use for the purpose of tracing images thrown on to paper placed at the bottom of the box. These primitive forms of the camera must be well known to all present. I name them only as affording some explanation for the use of the darkened room or tent. The next question which suggests itself is this : — Did they employ the camera in producing images on chemically pre- pared surfaces ? In fact, did they practice what we now name photography ? It is stated that in 1802 Wedgwood and Davy experi- mented with salts of silver on leather, and produced impres- sions of various objects. Now if we may be allowed to imagine that Mr. Boulton and his colleagues were acquainted with this effect of light on such substances, they might have reasoned on the phenomena, and prepared paper with these constituents — tannic acid, gelatine, and some salt of silver. Had they done so they might have produced a picture by sufficient exposure in the camera. One thing is certain, the pictures 7 and 8 have a plentiful coating of gelatine, albu- men, or some oilier substance on their surface.* * My son William Dancer tested this substanco aud pronounced it to be gum. 159 At this stage of the inquiry I should like to ask a question of those who have inspected a large number of these pictures. Do any of them show unmistakeable marks of the originals, such as we are all familiar with in photographic copies ? If this could be favourably answered, then photography of the present day would be benefited by the discovery of the means adopted in fixing these pictures. I much doubt if one of our best photographs on paper would contrast favourably with these pictures in the whites after a lapse of seventy years. But in my humble opinion photography has not been the agent employed in producing these pictures. Mr. Sidebotham had a portion of one picture presented to him, and he kindly shared this with me. In my experiments I found that the colouring matter forming the picture could be washed off like ordinary ink, without leaving a trace of any chemical action on the paper. Now if this portion of the picture be a genuine sample, it does not exhibit the ordi- nary characteristics of a photograph. On further consideration there are many reasons which would lead me to conclude that these pictures have been produced by some modification of mezzotint engraving, in which the camera had enabled the engraver to trace his out- line from the original to any scale required, giving him the correct outline drawing, the shading being an after process ; but the rapidity of production, and the low price charged, unfortunately excludes this process from the list of probabili- ties. Although mezzotint is said to be the most rapid method of engraving, I am compelled to abandon it or its modifica- tions, and pass on to some other process. Now if we do not believe in the photographic portion of the secret, and are not permitted to employ engraving on metal on account of the expense and labour, we find the field of speculation becoming somewhat limited. Now comes a very important question: — Did Mr. Boulton anticipate Senefelder in some process similar to lithography, employing metallic plates or metallic alloys? I can almost 160 imagine that such was the case. Even prepared paper surfaces, such as are named in Senefelder’s patent specifica- tion, dated 1801, might have been used at Soho. When we look at the rough hand-made paper on which these impres- sions are placed, and see the thick coating of gum or gelatine on the surface, the question then arises — Is this prepared surface necessary for taking up the ink or whatever was used ? or is it merely to smooth over the coarse wire lines in the paper ? We do know that the want of smooth paper inter- fered with the practice of lithography for a long period. Machine-made paper was a great improvement, but now paper is made especially for the purpose. After glancing over these processes, I am led to imagine that the following mode may in some degree serve to produce pictures similar to those before us : — Admitting that the impressions were touched up by hand, I think the camera was employed only for tracing the outline and reducing or enlarging the image to any required scale. The pictures Nos. 7 and 8 give good evidence of tracing. The shading would be an after process, having the original for a copy, the crayon employed being made of some resinous or fatty matter mixed with the colour — this production then to be used as a transfer on the prepared surface. In such pictures intended for painting, the ink would be light in colour — in others red or black, as the taste of the artist dictated. In this manner, as Senefelder states in his specification, the various styles of etching, stroke engraving, drawings in black and red chalk and aquatinta, &c., &c., could be imitated, and at small cost compared with any other known process. I shall now leave this very interesting inquiry in your hands. As an excuse for the brief and imperfect handling of the subject, I may state that it is only two days since I first saw the pictures, and I have not had sufficient time to work up the subject in a proper manner ; but if ray speculations serve to provoke a discussion amongst the members of the Section, its purpose will have been answered. 161 Ordinary Meeting, April 3rd, 1866. R. Angus Smith, Ph.D., F.R.S., &c., President, in the Chair. Messrs. Win. Brockbank and G. C. Lowe were appointed Auditors of the Treasurer’s accounts. Mr. Bin ney,F.R.S., said that he had observed the humming bird hawkmoth ( Macroglossa Stellnlarum ) during the past summer in far greater abundance than he ever remembered having seen it before. In the month of August, he saw upwards of a hundred of them in a garden near Grimsby, were they appeared to prefer the common lavender flower for food to any other in the place. Again in the first week of October, he observed upwards of twenty in a garden at Douglas, in the Isle of Man. Here they preferred to feed on heliotrope before other flowers. It was very interesting to watch these moths hovering over the flowers, and whilst on the wing extracting their food. They appeared very wary and shy after any attempt being made to capture them, but if you merely observed without making any attempt to molest them they would continue their feeding in confidence, and you could "watch them at your leisure. So a great deal of the shyness and caution for which the little creature has got the credit of, is probably more due to the persevering efforts of its enemies to capture it than any natural fear of man. A paper was read “ On a Logical Abacus,” by W. S. Jevons, Esq., M.A. . The author believed that this was the first attempt, or at all events, the first successful attempt, to reduce the pro- cesses of logical inference to a mechanical form. The purpose of this contrivance is to show the simple truth, and the perfect Pboceedings— Lit. & Phil. Society.— Voe, V. — No. 14 — Session 1865-6. 162 generality of a new system of pure Qualitative Logic closely analagous to, and suggested by, the mathematical system of logic of the late Professor Boole, hut strongly distinguished from the latter by the rejection of all considerations of quantity. This logical abacus leads naturally to the construction of a simple machine which shall be capable of giving with absolute certainty all possible -logical conclusions from any sets of propositions or premises read off upon the keys of the instrument. The possibility of such a contrivance is practically ascertained; when completed it will furnish a more signal proof of the truth of the system of logic embodied in it. Still the more rudimentary contrivance called the abacus will remain the most convenient for explaining the nature and working of formal inference, and may be usefully employed in the lecture room, for exhibiting the complete analysis of arguments and logical conditions, and the expo- sure of fallacies. The abacus consists of — 1. An inclined black board, furnished with four ledges, 3ft. long, placed 9in. apart. 2. Series of flat slips of wood, the smallest set four in number, and other sets, 8, 16, and 82 in number, marked with combinations of letters, as follows : — First Set. A A a a B b B b Second Set. a b C The third and fourth sets exhibit the corresponding com- binations of the letters A, B, C, 1), a, b, c, d} and A, B, C, U, E, a, b, c, d, e. 163 The slips are furnished with little pins, so that when placed upon the ledges of the board, those marked by any given letter may be readily picked out by means of a ♦straight-edged ruler, and removed to another ledge. The use of the abacus will he best shown by an example. Take the syllogism in Barbara : — Man is mortal. Socrates is man. Therefore Socrates is mortal. Let A = Socrates. B = Man. C - Moi-tal. The corresponding small italic letters then indicate the negatives. x a = not-Socrates, b — not-Man, c = not-Mortal, and the premises may be stated as A is B, B is C. Now take the second set of slips containing all the possible combinations of A, B, C, a, b, c, and ascertain which of the combinations are possible under the conditions of the premises. Select all the slips marked A, and as all these ought to be B’s, select again those which are not B, or b, and reject them. Unite the remainder, and selecting the B’s, reject those which are not C or c. There will now remain only four slips or com- binations : A a a a ' B B b b C C C c If we require the description of Socrates, or A, we take the only combination containing A, and observe that it is 164 joined with C, heuce the Aristotelian conclusion Socrates is mortal. We may also get any other possible conclusion. For instance the class of things not-Man or b is seen from the two last combinations to be always a or not-Socrates , , but either mortal or not-mortal as the case may be. Precisely the same obvious system of analysis is applicable to arguments however complicated. As an example take the premises treated in Boole’s Laws of Thought, p. 1^5. (1.) Similar figures consist of all whose corresponding angles are equal, and whose corresponding sides are propor- tional. (2.) Triangles whose corresponding angles are equal have their corresponding sides proportional, and vice versa. Let A — similar. B = triangle. C - having corresponding angles equal. D = having corresponding sides proportional. The premises may then be expressed in Qualitative Logic,* as follows : — A = CD. BC = BD. Take the set of 16 slips ; out of the A’s reject those which are not CD ; out of the CD’s reject those which are not A ; out of the BC’s reject those which are not BD ; and out of the BD’s reject those which are not BC. There will remain only six slips, as follows : — From these we may at once read off all the conclusions laboriously deduced by Boole in his obscure processes. We * See Pure Logie, or the Quality of Logic, apart from Quantity, by W. Stanley Jevons, M.A., London (Stanford), 1864. 165 at once see, for instance, that the class a, or “dissimilar figures, consist of all triangles (B) which have not their corresponding angles equal (c) and sides proportional ( d ), and of all figures not being triangles (5) which have either their angles equal (C) and sides not proportional ( d ), or their corresponding sides proportional (D) and angles not equal, or neither their corresponding angles equal nor corresponding sides proportional.” (Boole, p. 126.) The selections as made upon the abacus are of course subject to mistake, but only one easy step is required to a logical machine, in which the selections shall be made mechanically and faultlessly by the mere reading down of the premises upon a set of keys, or handles, representing the several positive and negative terms, the copula, conjunctions, and stops of a proposition. Mr. Jevons stated his opinion distinctly that these contri- vances possessed a theoretical rather than a practical importance. Like the analogous Calculating Machine of Babbage or Scheutz, the logical machine would hardly find practical employment for the present at least. But its value consisted in showing the true nature of logic as a system of analysis of the possible combinations of things, in short as the highest and simplest form of the doctrine of combinations. Not only would the deductive, and especially the inductive processes of logic be thus presented in a new and clearer light, but the relation of logic, the qualitative doctrine of combina- tions, to mathematics the quantitative doctrine of combinations, would be defined, and the abstract sciences thus brought into harmony and due subordination. In the description of his balance given in the last No. of the Proceedings, Dr. Joule omitted to mention a fixed support against which the scale rests when the counterbalance is removed. By this means the wires are kept constantly in the same state of tension, and are thus preserved from the derangement which might otherwise ensue. 166 MICROSCOPICAL AND NATURAL HISTORY SECTIONS. March 26th, 1866. A. G. Latham, Esq., President of the Sections, in the Chair. The following objects were exhibited Eight mounted specimens of hair of Australian animals for the cabinet ; one of them, a species of Phascogale, very remarkable. — Mr. Latham. A large collection of rare beetles from Ceylon, recently presented to the Natural History Society by Braybrooke, Esq. — Mr. Latham. Many specimens of remarkable foraminifera from Dogs Bay. — Mr. Linton. A sample of the Guano lately imported from Malden Island in the Pacific, for distribution among the members. — Mr. Latham. Dr. Alcock showed mounted specimens of Embryonic shells of Mollusca, including fifty species collected by him from Dogs Bay sand, and named by J. Gwyn Jeffreys, Esq. — He said he had in a former communication described the peculiar characters of Anomia in the young state, and shells of this kind are abundant in the sand. Pectens are also common, and six different forms which he had sorted out are referred by Mr. Jeffreys to the following species: — P. varius, opercularis, tigrinus, testce, similis, and maximus. Lima subauriculata and L. Loscombii are both rather scarce. Modiolaria discors in the young state is very common. Area tetragona, abundant ; Kellia suborbicularis, common ; Car- dimn ecliinatum, rare ; Cardium fasciatum, very common ; several species of Venus, frequent; and Saxicava rugosa, very abundant. Patella vulgata, Ilclcion pellucidum, and Tectura virginca with spiral caps are all common, the last 167 being very abundant. Another limpet-like shell without spiral cap, referred to in a former paper, is identified by Mr. Jeffreys as Ancylus fluviatilis. Emarginula fissura is rare, and of Fissurella Grseca, one specimen only has been found. Caecum glabrum with spiral attached is common, and sepa- rate spirals are abundant ; only one specimen of Aclis unica has been met with ; Eulimella nitidissima is common ; Homatogyra rota, rare ; Cerithiopsis ad versa, common. A few of the embryonic and partly grown shells of Aplysia depilans have been found, hut they are very scarce. In addition to the named specimens, a considerable number of other species not yet identified were exhibited. List of Embryonic Anomia ephippium. Pecten varius. „ opercularis. ,, tigrinus. „ testae. ,, similis. ,, maximus. Lima subauriculata. ,, Loscombii. Mytilus phaseolinus. Modiolaria discors. Area tetragona. Montacuta bidentata. „ ferruginosa. Kellia suborbicularis. Sphaerium corneum. Cardium echinatum. „ fasciatum. Venus lincta. Venus. Tellina tenuis. Scrobicularia alba. Lyonsia Norvegica. Thracia papyracea. Saxicava rugosa. Shells of Mollusca Patella vulgata. Helcion pellucidum. Tectura virginea. Emarginula fissura. Fissurella Graeca. Homatogyra rota. Caecum glabrum. Cerithium reticulatum. Cerithiopsis adversa. Scalaria communis. Aclis unica. Eulima distorta. Chemnitzia elegantissima. Odostomia unidentata. Eulimella nitidissima. „ acicula. Velutina laevigata. Lamellaria perspicua. Purpura lapillus ? Mangelia linearis. Gyllchna cylindracea. „ truncata. Aplysia dejiilans. Spirialis Flemingii. Ancylus fluviatilis. 168 PHYSICAL AND MATHEMATICAL SECTION. March 29th, 1866. Robert Worthington, F.R.A.S., Vice-President of the Section, in the Chair. Mr. Baxendell, F.R.A.S., communicated the following: — Results of Rain Gauge and Anemometer Observations made during the Year 1865, At St. Martin’s Parsonage, Castleton Moor, by the Rev. J. Chadwick Bates, M.A., E.R.A.S. Table I. 5-inch Gauges. 8-inch Gauges. Total Movement of Wind. 20 feet eleva- tion. 5 feet ole va- tion. I foot eleva- tion. 20 feet eleva- tion. 5 feet eleva- tion. 1 foot eleva- tion. January 3-m 3-492 3-874 3292 3-631 4050 7156 February 2344 2-493 2934 2-572 2-775 3033 5875 March 1055 1161 1-359 1-111 1-246 1-396 7275 April 1-337 1-377 1-444 1-377 1-410 1-471 7074 May 2-297 2-622 2-863 2-278 2-647 2-784 6934 June 0656 0668 0-659 0-670 0666 0-669 5213 July 3-224 3-407 3-546 3-260 3347 3112 5751 August 4-645 4-892 5099 4-733 4-862 4-941 5591 September 0-548 0-614 0-657 0-580 0628 0-652 4551 October 5-777 5-010 6-251 5-858 6030 6-230 6621 November 3-303 3-508 3-829 3-384 3608 3-774 6097 December 1-092 1-234 1-313 1158 1-207 1-299 6121 29-455 31-478 33-830 30-273 32057 88-714 74269 169 Table II. 1 No. of Days of Rain. Total Movement of the Wind. Mean Daily Movement of Wind on Days of Rain. No. of Fan- Days. Total Movement of the Wind. Mean Daily j Movement 1 of Wind j on Fan- Days. January 13 4394 338 18 2762 153 February 15 3622 241 13 2253 173 March. 11 2873 261 20 4402 220 April 8 2103 263 22 4971 226 May 18 4501 250 13 2433 187 ! June 4 1155 288 26 4058 156 July 14 2822 201 17 2929 172 August 16 3284 205 15 2307 153 1 September 2 530 265 28 4021 143 October 18 i 3847 213 13 2774 213 November 14 3958 282 16 2139 133 December 8 2709 338 23 3412 148 141 ! 35798 253-8 224 38461 171-7 From Table I. it will be seen that the total movement of the wind was greatest in the month of March, and least in September. In the year 1864 it was also greatest in March, but least in August. The total amounts in the quarterly periods of the two years were : — 1865. 1864. Winter 19152 miles. 19174 miles. Spring 21283 „ 20940 „ Summer 16555 „ 18111 „ Autumn 17269 „ 20088 „ Table II. shows that the mean daily movement of the wind on days of rain in 1865 was 253*8 miles; and on days without rain, 171*7. The numbers in 1864 were 251*6, and 179*4 respectively. The mean results for the quarterly periods, and their ratios, were : — Mean Daily Movement Mean DailyMovement of the Wind on Rainy Days. of the Wind on Fair Days. Ratios. Winter 298 156 0-52 Spring 256 214 0-83 Summer 213 160 0-75 Autumn 245 156 0-63 The ratios in 1864 were. Winter, 0*68 ; Spring, 0*82 j Summer, 0*72 ; Autumn, 0*60. It appears therefore from 170 the observations of the two years that the ratio of the mean velocity of the wind on days- when no rain hills, as compared with that on rainy days, varies least in the spring, and most in the winter quarter. Mr. W. L. Dickinson read a Paper containing the results of calculations relative to the Eclipse of the Sun, and to two Occupations of the star Aldebaran by the Moon, visible here this year. The calculations have been made for the Obser- vatory of Robert Worthington, Esq., F.R.A.S., Crumpsall, near Manchester, Lat. 55° 30' bO'^O N., Long. 0h 8m 56s,16 W. The Elements used in the computations have been obtained from the Nautical Almanac. The Partial Eclipse of the Sun, October 8, 1866, is partly visible at the Observatory, and xx. xxx, o. Begins 4 19 39 1 Mean Time at Greatest Phase 5 21 35 j Greenwich. At Crumpsall the Sun will set at 5h. 27m. Magnitude of the Eclipse (Sun’s diameter = 1 ) 0’480. Angle, from North Pole, of first contact, 43° I towards the West for Angle, from V ertex, of first con- j direct image, tact, 76° J The Occupations of the star a Tauri (Aldebaran) by the Moon. 1866. September 28th... November 22nd... Disappeaeance. Sidereal Time at Observatory. Mean Time at Observatory. Mean Time at Greenwich. Angle from North Ver- Point. tex. 1 h. in. s. 3 41 36 1 53 44 k. m. s. 15 10 56 9 47 6 h. m. s. 15 19 52 9 56 2 o o 84 75 73 44 1866. September 28tb . . . November 22nd... Keappeaeance. Sidereal Time at Observatory. Mean Time at Observatory. Mean Anglo from Time at | North Ver- Greemvich. 1 Point, tex. h. m. s. 4 51 41 2 51 55 ll. 111. s. 16 20 49 10 45 8 h. m. s. 0 0 16 29 45 295 303 10 54 4 310 j 290 171 The Angles are reckoned towards the right hand round the circumference of the Moon’s image as seen in an invert- ing telescope. Mr. Brothers, F.R.A.S., stated that when a solution of nitrate of silver, which, from long use, has become con- taminated with organic matter from collodion plates, is neutralized, or made alkaline with carbonate of soda, exposed to strong day-light in an evaporating dish, and heat applied, a scum is quickly formed on its surface. This scum, when broken by a puff of air exhibits, in a remarkable manner, all the appearances of solar spots as seen in good telescopes. So long as the current of air is continued the scum remains open at the spot, but immediately closes partially on the cessation of the cause, and streams of the film stretch across the opening, illustrating the bridges over the sun spots. At the same time a secondary scum commences to form at the edges of the opening, and may be called the penumbra, and in time closes the opening. The centre is occupied by the umbra formed by the carbonate of silver (white when first formed) which has in the course of the experiments turned black. It was found that when a current of the solution was forced upwards these effects could not be produced, and the film was not affected when a small body Avas dropped into it. When the solution has been exposed to the heat for a few hours the film becomes too thick to exhibit the experiment, and when cold the appearances described could not be pro- duced. This experiment was referred to merely as illus- trating the appearances of sun spots, and in no Avay as explaining their cause. At the same time it suggested the idea that if the luminous photosphere of the sun is formed of bodies, named by various observers, “ willow leaves” (Nasmyth), “rice grains” (Stone), “bits of straAv” (DaAves), and of the existence of distinct bodies of some kind on the visi- ble surface of the sun (here can now be very little doubt, they may be floating in a fluid sufficiently dense to sustain them, but at the same time easily thrust aside by some disturbing cause below the surface. The existence of an external cause at the surface of the sun being improbable, may not the cause of the sun spots arise from a current or force, such as the “ red flames ,” which are supposed to be connected with the formation of spots? This force acting on the “ willow leaves” would raise them from the level at which they may be sup- posed to float, they would slide under and over each other, and thus leave an opening; and, upon the gradual cessatiou of the disturbing cause, the tendency of the “ willow leaves *’ would be to gradually assume their former positions and close up the spots in a way similar to the closing of the film in the simple experiment referred to. Mr. Brothers also stated that, while observing the moon with his five-inch achromatic telescope at about eight o’clock on the evening of March 25th, he observed a small r/or/rbody cross the disc diagonally, from left to right, a little below the spot Copernicus. The motion was very rapid and similar to the passage of a luminous meteor across the field of view. He conceived it might be a meteoric body passing through space at a distance considerably beyond the limits of the earth’s atmosphere. 173 Annual Meeting, April 17th, 1866. R. Angus Smith, Ph. D., F.R.S., &c.. President, in the Chair. The following report of the Council was read by one of the Secretaries : — The Council have again the satisfaction to report that although the balance of the Treasurer’s account has been reduced from £360. 4s. 3d. on the 1st of April, 1865, to £269. 4s. 3d. on the 1st of April, 1866, the finances of the Society are nevertheless in a healthy state. Extra expendi- ture has been incurred during the past year for printing and publishing vol. 2, series 3, of the Society’s Memoirs ; binding books in the library ; printing a catalogue of the Society’s library ; and purchasing new books, and also volumes to complete imperfect sets. The number of ordinary members on the roll of the Society on the 1st of April, 1865, was 187. Five new members have been elected during the year ; and the losses have been by deaths, six ; resignations, one ; and defaulters, two. The number of members on the roll on the 1st of April, 1866, was therefore 183. The deceased members are — Rev. Thos. Buckley, M.A., Mr. James Joseph Dean, Mr. John Parry, Sir Benjamin Heywood, Bart., F.R.S., Mr. John Whalley, and Mr. Richard Hampson. Sir Benjamin Heywood, Bart., F.R.S., was one of the oldest members of the Society, having been elected on the 27th of January, 1815. He held the office of Treasurer for many years, and was one of the Trustees of the Society’s * Proceedings— Lit. & Phil. Society.— Vol. V.— No. 15— Session” 1865-6. 174 property. He took an active interest in local literary and scientific institutions, and was one of the founders of the Manchester Royal, and Mechanics’, Institutions. He held the presidency of the latter institution from 1824 to 1841. In 1831-32 he represented the county in parliament, and whilst in London became an intimate associate of the pro- minent literary and scientific men of the time. Mr. John Parry had been a member of the Society for 32 years, having been elected on the 26th of April, 1833. He was a constant attendant at the ordinary and sectional meet- ings of the Society, and took an active part in the formation of the Microscopical, Natural History, and Photographical Sections. He was the inventor of coloured signal lamps for railways, the first lamps of this kind having been made by the late Mr. Ford, of Cateaton-street, under his directions, and used on the Manchester and Leeds Railway. He had been forty-three years in the confidential employment of Messrs. Lockett and Co., the well known engravers to calico printers, and was one of the first to employ photography in connection with that business, in which he also introduced the electrotype process in 1839. His mechanical skill and ingenuity were displayed in the construction of a large solar microscope on a principle similar to that of the one exhibited at the Adelaide Gallery, London, about 1839 or 1840; in making a panoramic camera, camera bellows, apparatus for waxing paper, and for drying albumen plates ; and in cutting and polishing sections of fossils for microscopic slides. He was an enthusiastic photographer, and had been very success- ful in producing enlarged photographs of microscopic objects. In the summer of last year he visited the coast of Galway, where he succeeded in finding a rich deposit of Foraminifera containing many new species, descriptions and lists of which have been given by Dr. Alcock in the Society’s Proceedings. The several Sections of the Society have continued to ex- hibit their usual activity, and have furnished many important 175 communications to the Proceedings, and to the Memoirs of the Society. The admission of Sectional Associates has again been found to work satisfactorily, and the Council have therefore resolved that the system shall remain in force during another year. The following papers and communications have been read at the ordinary and sectional meetings of the Society during the past session : — October 3 rcl, 1865. — “On the Internal Heat of the Earth as a Source of Motive Power,” by Mr. George Greaves, M.R.C.S. “Note on the Eclipse of the Sun, October 19th, 1865,” by Mr. W. L. Dickinson. October 5th, 1865. — “On Photographs of the Eclipse of the Moon, October 4th, 1865,” by Mr. A. Brothers, F.R.A.S. “ On a Camera for outdoor work without a Tent,” by Dr. J. P. Joule, F.R.S., &c. October 12th, 1865. — “Rainfall at Eccles for 1864,” by Mr. Thomas Mackereth, F.R.A.S. October 16th, 1865. — “Notes on Atlantic Soundings,” by Mr. Joseph Sidebotham. “ Notes on Acherontia atropos,” by Mr. Joseph Sidebotham. “ Questions regarding the Life-History of the Foraminifera, sug- gested by Examinations of their Dead Shells,” by Mr. Thomas Aleock, M.D. October 11 th , 1865. — “Notes on the Origin of several Me- chanical Inventions, and their subsequent application to different piu’poses, Part I.,” by Mr. J. C. Dyer, Y.P. October 31$£, 1865. — “On Cooling and Ventilating the Workings of deep Coal Mines,” by Sir J. F. W. Herschel, Bart, M.A., D.C.L., F.R.S., &c. “ On Coresolvents,” by the Hon. Chief Justice Cockle, M.A., - » <2S: \2 o n 2-p o *131 . cJ'2.2 o OeJjwS cM O g B4-rQ O i&S o” 8 aS 2 B33 |oi .2 . o o MS|a 32°| © O fcfi Q, ^o-S'g = S.Oo«8 e'C « 5J3 CO I CO 1 OO ( ** r^jCOO <«£ . . *o O * ’■** CO OO OO ^ rH rH rH rH COrJt rH rH 6 O r3 • • • CM CO • • • o> tO : : -M • • • * / — — -A — ST rH rH J ! * E3 :<3”«8 185 :„ . -<* *? I <1 B a *C 0 1 =3 rfl .a r3 -2. IS II i-S 1.9 && s« Oco rH H C^co =*1 181 A paper was read “ On the Casting, Grinding, and Polish- ing of Specula for Reflecting Telescopes, Part I,” by James Nasmyth, C.E., Corresponding Member of the Society. In this, the first part of his paper, the author describes in considerable detail the methods and processes by which he produces speculum metal of the best quality, and casis, anneals, and rough-grinds a speculum of ten inches in diameter, his descriptions being illustrated by drawings of the apparatus he employs. In the second part of the paper he will describe the processes of fine-grinding, polishing, and figuring ; and will give directions for the general manage- ment and use of reflecting telescopes. His instructions are based upon the results of thirty years’ experience in the art of working specula, and will, he believes, enable any zealous amateur to make for himself, at a moderate cost, a really good and useful reflector. PHOTOGEAPHICAL SECTION. April 12th, 1866. Dr. J. P. Joule, F.R.S., &c., Vice-President of the Section, in the Chair. A paper was read entitled “Note on the First Use of Hyposulphite of Soda in Photography,” by A. Brothers, F.R.A.S. 182 During an investigation into the early history of photo- graphy, I met with the statement that Daguerre used hyposulphite of soda in his process for fixing the pictures, and also that in Mr. Talbot’s patent the use of that substance was included. I was under the impression that Sir John Herschel had pointed out that hyposulphite of soda would fix the photographic image, but was unable to ascertain where or when the discovery was first published. In order to determine this point I wrote to Sir John Herschel, requesting him to inform me whether the discovery was his, and the date when it was published. To these questions I received the following reply : — Colingwood, October 29, 1864. Sir, I think I may very fairly claim the discovery of the hyposulphites as fixing agents, as I believe I was the first to call the attention of chemists to that class of salts and their peculiar habitudes, especially in relation to the insoluble salts of silver. In my paper “ On the Hyposulphurous Acid and its Com- pounds,” which bears date Jan. 8, 1819, and which appeared in Brewster and Jamieson’s Edinb. Phil. Journal, 1819, occur these words : — “ One of the most singular characters of the hyposulphites is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantities in permanent solution.” (page 11.) “ Hyposulphite of potash. — It dissolves muriate of silver even when very dilute, with great readiness.” (p. 19.) “ Hyposulphite of soda Muriate of silver newly precipi- tated dissolves in this salt when in a somewhat concentrated solution in large quantity and almost as readily as sugar in water.” (p. 19.) “ Hyposulphite of strontia Like the rest of the hypo- sulphites it readily dissolves muriate of silver, and alcohol preci- pitates it as a sweet syrup.” (p. 21.) 183 ‘ Hyposulphite of silver. — Muriate of silver newly precipitated is soluble in all liquid hyposulphites, and, as before observed, in that of soda with great ease and in large quantities. This solution is not accomplished without mutual decomposition, as its intense sweetness proves — a sweetness surpassing that of honey, and dif- fusing itself over the whole mouth and fauces, without any disagreeable or metallic flavour.” (p. 27.) In a second paper on the same subject, which appeared in the same jonmal, vol. 1, p. 396 et seq., it is shown ( inter alia) that the affinity of this acid for silver is such that oxide of silver readily decomposes hyposulphite of soda and likewise the soda in a caustic state, “ the only instance, I believe, yet known of the direct dis- placement of a fixed alkali vid humidd by a metallic oxide.” (p. 397.) “ Hyposulphite of ammonia and silver. — Its sweetness is unmixed with any other flavour, and so intense as to cause pain in the throat one grain communicates a perceptible sweetness to 30,000 grs. of water.” (p. 399.) In a third communication, dated November, 1819 — “The habi- tudes of this acid with the oxide of mercury are not less singular than its relation to that of silver.” — “ The red oxide is readily dissolved by .... , hyposulphite of soda, while the alkali is set at liberty in a caustic state,” &c. &c. The very remarkable facts above described I have reason to believe attracted a good deal of attention at the time, and thence- forward the ready solubility of silver salts, usually regarded as insoluble, by the hyposulphites was familiar to every chemist. It would not therefore be surprising if Daguerre tried it to fix his plates ( i.e . to wash off the iodide coating); but I have been informed, though I cannot cite a printed authority for it, that at first he fixed with ammonia, or with a strong solution of common salt. For my own part the use of the hyposulphites was to myself the readiest and most obvious means of procedure, and presented itself at once. My earliest experiments were made in January, 1839, and in my notebook I find : — “Exp. 1012. — 1839, Jan. 29. Experiments tried within the 184 last few days, since hearing of Daguerre’s secret, and also that Fox Talbot has got something of the same kind.” [Here follow some trials of the relative sensitiveness of the nitrate, carbonate, acetate, and muriate of silver. I should observe that at that time I did not even know what kind of pictures Daguerre had pro- duced. This process was not revealed till August, 1839.] “Exp. 1013. — Daguerre’s process — attempt to imitate. Requi- sites— 1st very susceptible paper — 2nd very perfect camera — 3rd means of arresting further action. Tried hyposulphite of soda to arrest the action of light by washing away all the chloride of silver or other silvering salt — succeeds perfectly. Papers half acted on, half guarded from the light by covering with pasteboard, were withdrawn from sunshine, sponged over with hyposulphite, then washed in pure water, dried, and again exposed. The darkened half remained dark, the white half white, after any exposure, as if they had been painted with sepia.” “Jan. 30, 1839. — Formed image of telescope with the aplanatic lens .... and placed in focus paper with carbonate of silver. An image was formed in white on a sepia colored ground .... which bore washing with hyposulphite of soda, and was then no longer alterable by light. Thus Daguerre’s problem is so far solved,”