ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



283 



(4,000,000 times), even the Times (28th January) signalling specially 

 the fact that the " eye of the smallest sewing needle made appears 

 to be about 6 feet long by 4 feet wide, the needle itself appearing 

 to be about 20 feet thick. From this it will he judged how well the 

 minutest details in the minutest specimens are brought out " (!) 



Most of the writers are not content to limit the value of such an 

 instrument to the display of objects to large audiences, where the 

 inferiority of the display is to some extent compensated for by the 

 increased number of spectators who can see the objects at the same 

 time, but evidently suppose that the increase of the magnification 

 represents a proportionate increase in the scientific value and capacity 

 of the instrument, and that by the use of "Giant Electric" Micro- 

 scopes we are brought many degrees nearer to the vision of the 

 ultimate molecules of matter than we are when sitting at home with 

 a student's Microscope only. 



The Standard of 28th January says, " But although this great 

 Microscope can make the eye of the smallest sewing needle apparently 

 a huge orifice some seven feet 



by five in dimensions, yet the Fio. 32. 



component particles of the 

 tissues of either animal or 

 vegetable organisms cannot be 

 even yet made visible, and the 

 minute divisions of matter 

 would remain unknown, so far 

 as the sight is concerned, and 

 would be an inscrutable mystery, 

 except for the deep reasonings 

 of the educated human mind ; " 

 while the Norwood Review asks 

 " What assistance, for instance, 

 may not surgeons derive from 

 it in the study of nosology? 

 It is safe to predict that Science 

 in her onward march will find 

 a valuable accessory in the 

 " Giant Electric Microscope " ! 



ToUes's Student's Micro- 

 scope — Fig. 32 is given by Dr. 

 L. Dippel in the latest edition 

 of his 'Das Mikroskop' (p. 541) 

 but without the explanation 

 that it represents not a modern 

 arrangement, but one of the 

 earliest forms of Microscope 

 devised by the late E. B. 

 Tolles, the peculiarity of which was that the rack of the coarse 

 adjustment was cut on a rod attached at both ends to the body-tubo 

 and passed through the straight part of the limb where the pinion 

 acted upon it. We believe this plan was adopted for economy of 

 manufacture, as the body-tube sliding in a socket required very 



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