THE MICROSCOPE. 



MALASSEZ'S IMPROVED COMPTE-GLOBULES. 



\:\ C. ii. ST( (WELL, 



SOME four months ago an order was given to James W. Queen 

 c\r Co. to procure from Verick, of Paris, one of these corpuscle- 

 counters. I regret that the apparatus, that has just arrived, cannot 

 be fully illustrated with this description. If possible the cuts will be 

 procured and the illustrations given in some future number. It is 

 with this instrument that I intended to conduct a series of exhaus- 

 tive experiments, the results of which were to be imbodied in a 

 paper, already "announced for the meeting of the American Society 

 in Chicago. A few months illness, however, overthrows many 

 plans, and doubtless the Chicago meeting will be a thing of the past 

 before the eye can be placed again over the tube of the microscope- 



The following description of the instrument is taken largely 

 from the Royal Microscopical Jour mil for August, 1X82: 



This improved apparatus consists of a thick brass slide, having 

 in the center an aperture, into which is fixed a circular glass block- 

 about a centimetre in diameter, with its upper surface level with the 

 top of the slide, and surrounded by a groove about half the thick- 

 ness of the slide in depth. Outside this groove are three pointed 

 metal screws, equi-distant from each other, the elevation of which 

 above the surface of the slide is exactly \ mm. In the center of the 

 glass block the squares are drawn in which the corpuscles are 

 counted. The sides of these are ? 1 (7 mm., and they are arranged in 

 groups of twenty. 



To facilitate lowering the cover-glass so as to be exactly hori- 

 zontal, Malassez devised the frame to the underneath part of which 

 the edges of the cover-glass are attached by a little water or saliva. 

 The frame is supported on two arms, attached to one flange of a 

 hinge, the other flange being secured to the side by a clasping screw. 

 The frame with the cover-glass is raised or lowered by the longer of 

 the two arms, and the operation may be quickly performed. A 

 small spring clip keeps the whole down, so that there is no danger 

 of the cover being raised or displaced. 



The whole apparatus, in a neat morocco case, costs about 

 $25.00. 



