70 



NA TURE 



[_May 19, 1 88 1 



last year ; and the donations 33/. 2S., as ajainst 18/. There had 

 been several large legacies realised, amongst them one of 4050/. 

 from Mrs. George Oakes. 



Manchester. — We understand that a sum of 1500/. has 

 been offered by a benefactor to the Council of 0\4ens 

 College for five fellowships of 100/. a year, each renewable 

 for a second or third year, the conditions being that they 

 shall be awarded on evidence given by the candidates of 

 their past work in literature or science, and on their satis- 

 fying the electors as to their subsequent devotion to original 

 work. The scheme is as yet only under consideration. We 

 likewise understand that Mr. Waterhouse is preparing plans 

 for completing a portion of the buildings required for Owens 

 College, including mu eums for natural history, geology, and 

 mineralogy, and for the lecture-rooms and laboratories required 

 for the professors of the above subjects. 



On Saturday next (May 21) Prof. Boyd Dawkins, F.R. S., 

 will begin the seventh series of Field Lectures in Geology, 

 at Miller's Dale Station, Derbyshire. That and the two fol- 

 lowing Saturdays will be devoted to the examination of 

 the Carboniferous rocks of the Pennine Chain. On Saturday, 

 June 9, the class will visit the British Museum (natural history) 

 under the guidance of Dr. Woodward, F.R.S., for the study of 

 the mammalia associated with Pleistocene Man. On June 10 the 

 brickfields at Crayford and Erith, in Kent, will be visited under 

 the guidance of Mr. F. C. Spurrell ; and on the nth the subject 

 of the Antiquity of Man will be finished by an examination of 

 the collections of prehistoric archaeology in the British Museum 

 (Bloom^bury). 



The Queen has directed letters patent to be passed under the 

 Great Seal granting and declaring that the degrees of Bachelor 

 and Master of Arts and Bachelor and Doctor of Medicine, of 

 Laws, of Science, and of Music, gr.mted or conferred by the 

 University of Adelaide, South Australia, on any person, male or 

 female, shall be recognised as academic distinctions and rewards 

 of merit, and be entitled to rank, precedence, and consideration 

 in the United Kingdom and' in the colonies and possessions of 

 the Crown throughout the world, as fully as if the said degrees 

 had been granted by any university of the United Kingdom. 



SCIENTIFIC SERIALS 



Journal of the Royal Microscopical Society for April, 18S1, 

 vol. i. ser. ii. part 2, contains— Prof. P. Martin Duncan, on a 

 Radiolarian and some Microspongidae from considerable depths 

 in the Atlantic Ocean (plate 3). —Dr. Lionel S. Beale, the Presi- 

 dent's address. — Prof. E. Abbe, on the conditions of orthoscopic 

 and pseudoscopic effects on the binocular microscope. — A. D. 

 Michael, on a species of Acarus believed to be unrecorded (plate 

 4). — Prof. E. Abbe, on the estimation of aperture in the micro- 

 scope. The summary of current researches, pp. 217-364. — Pro- 

 ceedings of the Society. (In the summary of current researches 

 appears a memoir by Mr. Crisp, "On Aperture, Microscopical 

 Vision, and the Value of Wide- Angled Immersion Objectives," 

 in which the whole subject is very exhaustively and clearly put.) 

 Aiiiiakn dcr Physik umi C/icmie, No. 4. — Experimental in- 

 vestigation of the connection between refraction and absorption 

 of light, by E. Ketteler. — On the ratio of intensity of the two 

 sodium lines, by W. Dietrich. — On the condensation of gases 

 on surfaces in their relation to pressure and temperature, by H. 

 Kayser. — Influence of pressure on the surface-tension of liquids, 

 by A. Kundt. — Variations of the vapour-density of some esters 

 with pressure and temperature, by P. .Schoop. — On differences 

 of tension between liquids touching each other, with reference 

 to concentration, by E. Kittler. — On electric ring-figures and 

 their alteration of form by the magnet, by E. Reitiinger and 

 F. Wachter. — On the divergence of Ampere's theory of mag- 

 netism from the theory of electromagnetic forces, by J. .Stefan. 

 — On some remarks of Ilerr C. Neumann on electrodynamics, 

 by R. Clausius. — The law of Clausius and the motion of the 

 earth in space, by E. Budde. — On the extent of the electric ex- 

 pansion in glass and caoutchouc, by Dr. J. Korteweg and V. A. 

 Julius. — The glass plate battery, byTh. Erhard. — Some remark- 

 able properties of flames, by W. Holtz. 



American yournal of Science, April. — Monograph by Prof. 

 Marsh on the Odontornithes, or toothed birds of North America, 

 by G. B. Grinnell. — On some elements in orographic displace- 

 men', by W. J. McGee. — On the indices of refraction of certain 

 compound ethers, by J. H. Long. — On the Whitfield County, 



Georgia, meteoric iron, by W. E. Hidden. — The basin of the 

 Gulf of Mexico, by J. E. Hilgard. — On the geology of Florida, 

 by E. A. Smith. — The magnetic survey of Missouri, by F. E. 

 Nipher. — American sulpho-selenides of mercury, by G. J. Brush. 

 — Analysis of Onofrite from Utah, by W. J. Comstock'. — Effect 

 of great cold on magnetism, by J. Trowbridge. — Channel 

 fillings in Upper Devonian shales, by H. S. Williams. — A new 

 order of Jurassic reptiles (Cjeluria), by O. C. Marsh. — .Dis- 

 covery of a fossil bird in the Jurassic of Wyoming, by the same. 

 — American pterodactyls, by the same. 



Journal of the Franklin Institute, March. — Experiments with 

 the Perkins machinery of the Anthracite, by Mr. Ishervvood. — 

 The wearing power of steel rails in relation to their chemical 

 composition and physical properties, by Dr. Dudley. — Note on 

 steam cylinders, by Prof Marks. — Novel mode of originating an 

 index wheel, by Dr. Grimshaw. — The polarisation of sound and 

 the nature of vibrations in extended media, by Prof. Robinson. 

 — Gyroscope model for class-illustration, by Dr. Rand. 



Reale htittito Lombardo di Science e Lcttere. Rendiconti, 

 vol. xiv. fasc. vii. — Grafts of the vine, by Count Trevisan. — 

 On the determination of maximum moments, &c. (continued), 

 by Prof. Clericetti. — On two rare helminths of reptiles, by Prof. 

 Pavesi. 



SOCIETIES AND ACADEMIES 

 London 



Royal Society, April 28. — "The influence of Stress and 

 Strain on the Action of Physical Forces." By Herbert Tomlin- 

 son, B.A. Communicated by Prof. W. Grylls Adams, M.A., 

 F.iR.S. Parti. — Elasticity. " Young's Modulus." 



The values of " Young's modulus " were determined for several 

 metals by a method devised by Sir W. Thomson. 



A large number of experiments with different loads were made, 

 and after a great many unsuccessful attempts to account for cer- 

 tain discrepancies which could not be explained away as errors 

 of observation, the following facts were elicited : — 

 ~ I. After a wire has suffered permanent extension, the tempo- 

 rary elongation which can be produced by any load becomes less 

 as the interval between the period of permanent extension and 

 that of applying the load becomes greater. 



2. This increase of elasticity is greater in proportion for large 

 loads than for small ones. 



3. The increase of elasticity takes place whether the wire be 

 allowed to remain loaded or unloaded between the period of 

 permanent extension and that of the testing for the elasticity. 



4. The rate of increase of elasticity varies considerably with 

 different metals ; with some the maximum elasticity is apparently 

 attained in a few minutes, and with others not till some days 

 have elapsed, iron and steel being in this last respect very 

 remarkabl«. 



5. The elasticity can also be increased by heavily loading and 

 unloading several times, the rate of increase diminishing with 

 each loading and unloading. 



6. A departure from " Hooke's law" more or less decided 

 always attends recent permanent extension, even when the 

 weights employed to test the elasticity do not exceed one-tenth 

 of the breaking weight. 



7. This departure is diminished very noticeably in the case of 

 iron, and much less so in the case of other metals, by allowing 

 the wire to rest for some time either loaded or unloaded ; it is 

 also diminished by repeated loading and unloadmg. 



The effect of permanent extension on the value of "Young's 

 modulus " was tried according to the direct method for iron and 

 copper, and indirectly for most of the metals. 



Prom both the direct and indirect methods results were 

 obtained which showed : — 



1. That, in all metals, provided the wire has not been kept 

 heavily loaded for some time before testing, permanent extension 

 produces decrease of elasticity, if the strain be not carried beyond 

 a certain limit. 



2. That, if the extension be earned beyond the above-men- 

 tioned limit, further permanent increase of length causes increase 

 of elasticity. 



3. That, in the case of iron, heavy loading for some time <o 

 increases the elasticity that, even when the extension would have 

 caused diminution of elasticity without such continued loading, 

 the latter will, if sufficient time be allowed, change this diminu- 

 tion into an increase ; in the case of copper this is not so. 



The effect of suddenly chilling steel heated to a high tempera 



