THE MICROSCOPE. 147 



The particles were shown to take four characteristic forms: Scat- 

 tered chips, windrows of fine particles, filaments or filaments of cir- 

 cular form. The subject of resolution of fine lines is discussed. 

 Who accepts the following proposed test? "With great respect for 

 the honest belief of several microscopists, who claim to have re- 

 solved Fasoldt's band as high as 152,000 to the inch, I must yet hold 

 to the opinion that in no case has the resolution been proved by a 

 test which will be generally accepted by microscopists. There is 

 one test and only one, which is absolutely decisive, viz. : the one 

 proposed originally by Nobert, that of ruling a definite number of 

 lines in a band of given fineness, and keeping the number secret 

 until the microscopist could give the correct count, not merely in 

 one instance but in several." The following concerning the power 

 of the eye, is worth thinking about: "At present the unaided eye is 

 a not very unequal competitor of the microscope in the matter of 

 simple vision. In fact, there are certain phenomena connected with 

 this question which can be better studied by the unaided eye than 

 under the microscope. I believe it to be possible to see under the 

 action of sunlight what cannot be seen under the objective. * * * 

 I will not undertake to say how fine lines traced upon metal can be 

 seen, but I suspect that the limit of naked-eye visibility is far be- 

 yond the capacity of ruling." 



Among the new or improved apparatus described were the fol- 

 lowing: A New Microscope, with Concentric Movements, by Gov. 

 J. D. Cox; A New Binocular Arrangement, by Edward Bausch; A 

 Modified Spitzka Microtome, by Dr. V. S. Clevinger, and A Solar 

 Microscope and Stereopticon, with ether-oxygen Light, by L. 1). 

 Mcintosh. 



Dr. F. M. Hamlin discussed in an able way the medico-legal 

 subject, The Microscopical Examination of Seminal Stains. He had 

 found, the method given in the manuals unsatisfactory, and had used 

 with success the following : " If the stain is upon thin cotton, linen, 

 silk or woolen fabric, cut out a piece about one-eighth inch square, 

 lay it upon a slide previously moistened with water, and let it soak 

 for half an hour. Then unravel or fray out the threads at the cor- 

 ners, put on a cover-glass, press it down firmly, and submit to the 

 microscope. If the fabric is of such a nature that it cannot be thus 

 examined, fold it through the centre of the stain, and with a sharp 

 knife shave off the projecting edge thus made, catching upon a 



