HA RDWl CKE ' S S CIENCE- G O SSI P. 



17 



We regret to hear that Professor Owen's health 

 has obliged him to resign his post as Superintendent 

 of the Natural History Department of the British 

 Museum. 



Under the title of " The Botanic Stand," Mr. 

 David Bogue has published a brochure by Thomas 

 Twining, price bd., in which is set forth the easy way 

 in which the natural orders of plants might be learned 

 by means of living specimens arranged in stands. 



We have received a copy of Mr. T. M. Reade's 

 "Traverse of the Yorkshire Drift," originally read 

 before the Liverpool Geological Society. The 

 "Traverse" extends from Ribblesdale across the 

 Pennine Chain, and the Vale of York to Scar- 

 borough. 



What can be done by the humblest workers has 

 recently been demonstrated in the case of Messrs. 

 Robert Law and James Plorsfall, who for three years 

 carefully and tediously explored the surface of the 

 millstone grit moors between Todmorden and 

 Marsden, for neolithic flint implements. They 

 lound no fewer than eighty-one, including stone 

 hammers, arrows, scrapers, lances, &c. The results 

 have been communicated in a paper (illustrated) read 

 before the Geological and Polytechnic Society of 

 Yorkshire. 



A REALLY scientific article on "Cremation," by 

 Mr. W, H. France, appeared in the last number of 

 ■" The Midland Naturalist." 



A CAPITAL paper on "The Geology of Central 

 Australia " appeared in the November number of 

 " The American Naturalist," by Edward B. Sanger, 

 who has explored the district. He shows how the 

 •continent of Australia has been gradually built up. 



Mr. Thomas Bolton, the well-known and enter- 

 prising provider of microscopic material, has sent 

 us a copy of his "Popular Account of the Fish's 

 Nest." It is illustrated by sketches showing the de- 

 velopment of the stickleback from its earliest stage 

 in the egg, and is accompanied by a notice of the 

 anatomy of the fish by Mr. J. E. Ady. 



Dr. Lang's" Butterflies of Europe" has just 

 reached the issue of its sixteenth part, and is devoted 

 to the various species of the genus Erebia, all of 

 which are illustrated by the exquisite coloured 

 drawings which have already rendered this work 

 noteworthy. 



Part 5 of Dr. Greene's " Parrots in Captivity " 

 has been issued by Messrs. Geo. Bell & Sons. It 

 •describes Barraband's parakeet, the red-winged 

 parakeet, and the Turquoisine, each of which is 

 illustrated by a beautiful coloured plate. 



At the meeting of the American National Academy 

 of Science recently held in New Haven for a few 

 days' session, the most important paper appears to 



have been read by Dr. Graham Bell, upon the 

 " Formation of a Deaf Variety of the Human Race," 

 in which he spoke against isolating deaf-mutes from 

 ordinary children, and the greater benefit which 

 would ensue from their being educated together, and 

 taught to speak by lip-signs, instead of the old sign 

 language. 



MICROSCOPY. 



Photographing Microscopic Objects. — At a 

 recent meeting of the Academy of Medicine in 

 Ireland, Dr. Dickenson read a note on the "Art of 

 Photographing Microscopic Objects," exhibiting a 

 number of specimens produced by himself and' the 

 apparatus used for the purpose. His apparatus con- 

 sists of three parts — the first, an inexpensive magic 

 lantern, illuminated by a triplex petroleum lamp 

 with the ordinary combination of lenses, and an 

 extra tube with a small bull's-eye condenser ; the 

 second, a microscope, placed horizontally without 

 the eyepiece ; and the third, a frame to hold the 

 glass screen for focussing the image, and to receive 

 the sensitised plate when photographing. The 

 period of exposure was from eighteen seconds to two 

 hours. Dr. Hayes congratulated Dr. Dickenson on 

 the great simplicity of the apparatus, and on the 

 results which it produced. He had no doubt that if 

 the electric light could be applied to it there would 

 be nothing to compare with it. Its use with a light 

 intense and strongly actinic would be a great advan- 

 tage ; for the illumination could be cut down by 

 diaphragms, and the sharpness and depth of the 

 image increased. W^ith the electric light he had got 

 pictures up to 300 diameters taken in four seconds, 

 and with the oxyhydrogen lamp pictures could be 

 obtained in from ten to twenty seconds. 



Mr. Hugh Powell. — We regret having to 

 announce the death of this well-known microscopist 

 (of the well-known firm of Powell & Lealand), at the 

 advanced age of eighty-five. How long he has been 

 before the world in connection with microscopy is 

 shown by the fact that in the year 1834 he was 

 awarded a silver medal by the Society of Arts, for a 

 stage for the microscope. Lately he has been chiefly 

 distinguished for his "fiftieth," and other high 

 powers. 



Drawing from the Microscope. — E. T. D., in 

 Science-Gossip for November, in his article, makes 

 a difficulty in the use of the neutral tint reflector 

 where none really exists. He has but to turn his 

 slide over, i.e. cover downwards, on the stage to 

 make his outlines, and then put his slide right way up 

 when he fills in his detail freehand. He will thus 

 have identically the same presentation of his subject 

 in each case. I do not agree with his remarks depre- 



