2i 4 



SCIEXCE-GOSSIP. 



MICROSCOPY, '! ii! 







CONDUCTED BY F. SHILLIXGTOX SCALES. F.R.M.S. 



Royal Microscopical Society. — The first 

 meeting of the Royal Microscopical Society for 

 the winter session took place on October 17. Mr. 

 Carruthers. F.R.S.. in the chair. Dr. Hebb showed 

 samples of stains for microscopic purposes pre- 

 pared in solid form by Messrs. Burroughs. Wellcome 

 & Co. These stains were noticed in this journal 

 (vol. vi. p. 247) when they were first offered for 

 sale. Messrs. R. ><c J. Beck exhibited their new 

 - London " microscope, noticed in this journal last 

 month (ante, p. 184). Mr. F. W. Watson Baker 

 gave an exhibition of slides and models illustrating 

 the structure and development of skin. Mr. Yesey 

 said the Society was greatly indebted to Mr. Watson 

 Baker for giving this very excellent exhibition at 

 comparatively short notice. Mr. Karop said he 

 had oidy been able to glance at a few of the speci- 

 mens exhibited, and he regretted there was no one 

 present to discuss the subject, because several new- 

 points had recently been recognised by histologists 

 in the structure of the skin, and it was rather a 

 pity that the opportunity should be lost of having 

 these demonstrated by some one who had made a 

 study of this important and complicated tissue 

 system. Mr. Yesey said that since the last meeting 

 the Society had lost by death a Fellow very well 

 known to many— Mr. Richard Smith. He had 

 devoted his attention to the study of diatoms, and 

 was continually devising new contrivances for use 

 in connection with the microscope. He had like- 

 wise undertaken important investigations in the 

 germination of wheat, and had made a large 

 number of observations and experiments in con- 

 nection with the subject, and published a book 

 relating to it. He would probably be best known 

 as the inventor and patentee of Hovis flour. The 

 President said he regretted to have to announce 

 that the Society had also recently lost by death 

 several other Fellows, one of whom. Mr. Edward 

 George, was personally known to him. He had 

 prepared a short memoir of Mr. George, which he 

 would read to the meeting. The secretary an- 

 nounced that Mr. Millett had forwarded part ix. of 

 his Report on the Foraminifera of the Malay 

 Archipelago, which was printed in the October 

 number of the Journal. 



Calces of Fracture of Sieel Rails.— The 

 value of the microscopical examination of steel 

 will be brought prominently before the public by 

 the recently issued report of the Board of Trade 

 committee appointed to examine into the cause of 

 fracture of a steel rail at St. Xeots station on 

 December 10th. 1895. by which a serious accident 

 happened to the down Scotch express. The report 

 itself, dealing as it does with various experimental 

 work undertaken by well-known experts, is some- 

 what inconclusive, but the microscopic examination 

 by Sir William Roberts-Austen gave resnlts of the 

 utmost interest and value. Briefly stated, it may 

 be said that, according to this eminent authoritv. 



good rail steel consists of " ferrite." or iron free 

 from carbon, and '• pearlite."" which is a mixture of 

 alternate bands of ferrite and '■ cementite," the 

 carbide corresponding to the formula Fe 3 C. Well- 

 developed pearlite with a conspicuous banded 

 structure is readily shown microscopically, and 

 is characteristic of good rail steel. When, how- 

 ever, steel is hardened by "quenching," pearl- 

 ite is absent, and " martensite," which consists of 

 interlacing crystalline fibres without banded struc- 

 ture, takes its place. Sir William Roberts- As- 

 says that •• the presence of martensite in a rail 

 should at once cause it to be viewed with extreme- 

 suspicion, as showing that the rail is too hard 

 locally to be safe in use." The broken rail at Si 

 Keot's showed an outside layer of martensite one 

 hundredth of an inch thick. The report deals 

 further with minute cracks found in this and other 

 rails, and the enormous increase in liability to 

 fracture occasioned thereby, and one conclusion 

 drawn is that patches of martensite can be pro- 

 duced in a rail, when in use. by local treating caused 

 by skidding, foUowed by the rapid extraction of 

 heat by the cold rail. It is thus evident that the 

 microscope will prove to be an increasingly valu- 

 able means of studying the complex structure of 

 steel. For this purpose and for the examination of 

 alloys it is used, and already a quite voluminous 

 literature is growing up around the subject. 



Number of Species of Plaxts. — Professor S. 

 H. Yines. in his opening address to the Botanical 

 Section of the British Association at Bradford, 

 gave some interesting figures as to the number of 

 species of plants at present known. The figures 

 may be tabulated as follows : — 



(Dicotyledons 7 ; .i 

 Monocotyledons .. .. 19.600 

 Gymnospenns ;.^£ 

 

 100.-2«> 

 Subsequent additions . . 5.011 

 105,231 



IFilicinae (including Isoetes) 

 about . . . . ~ . . . . 3,000 

 Lycopodinae, about . . . . 432 

 Equiatinae. about . . . . 2u 

 3.452 



(Musci 4,609 



Brvophvta \ Hepaticae 3,041 



( 7.650 



/ Fungi (including Bacteria) . . 39,663 



I Lichens . . 5.600 



Thallophyta J Algae (including 6.000 Dia- 

 toms).. .. .. .. 14,000 



{ 59,263 



Making a grand total of .. .. "175,596 



which, when compared with the 10,000 species of 

 plants known to Linnaeus in the latter half of the 

 last century, show how vast have been our additions 

 to the knowledge of plants. The amount of work 

 for microscopists, especially in the latter sections, 

 appears to be u nli mited. 



W: Watson i: Sons' New Catalogue. — 

 Messrs. W. Watson &: Sons, of High Holborn, have 

 sent us a copy of their new catalogue, which seems 

 to contain almost everything necessary to the work- 

 ing microscopist, and will be useful to all who are 

 interested in microscopy. The catalogue is a dis- 

 tinct improvement upon its predecessors. It con- 

 tains detailed descriptions, and illustrations of the 

 details, working parts, and modes of fitment and 

 adjustment of the various microscopes made by 

 the firm, ranging from the well-known and beauti- 

 ful '• Yan Heurck " microscope to the modest but 



