RECORDS. 



121 



This book must not be lost or misplaced. The advantage of having the serial 

 number written also on the bottle containing the stock of preserved material is ver}- 

 evident if a thing of this sort ever happens. The serial number is written on one 



edge of the slide-box, and serves to identify it (fig. 103). ^ 



Some record besides a mere number should also be placed 

 on the slide-boxes. All the slides within bear this num- 

 ber, c. £-., 256, and also a 

 series number of their own, 

 /. <?., I to 25. The slide- 

 boxes are then filed awa\' 

 on shelves either serially 

 or in groups, according to 

 the parasite. Slides con- 

 taining particularly good 



fields are marked X, and wdien the best fields are 

 finally decided upon their location is recorded as de- 

 termined on the mechanical stage. In case a dozen 

 or more serial sections are included on one slide the 

 the extra good ones are marked X on the first exam- 

 ination, and the others 0, as shown in fig. 113. 

 When one of these sections has been drawn or photo- 

 graphed, the X is underscored or inclosed by a circle. 

 This method enables one to keep track of any num- 

 ber of sections. Free-hand sections may be made with the Torrey razor showm in 

 fig. 114D. This is altogether the best razor the writer has used. When ver}- 

 duU it ma}' be sharpened on an India oil-stone. These stones are said to be made 

 of a mixti;re of carborundmn and clay, baked at a high temperature. They may be 



Fig. llO.t 



.# 



Fig. 109.* 



Fig, lILt 



had of the Norton Emery Wheel Company, Worcester, Mass., in three grades of fine- 

 ness, the finest being usually coarse enough for the dullest razors. The size needed 

 is 8 by 2 by i inch. The finishing may be done on an Arkansas oil-stone, with a 



*FiG. 109. — Coplin's staining jar. .A.bout one-half actual size. 



fFiG, no. — Cross-section of Coplin's staining jar. About actual size, 



|FiG. III. — A series of Coplin's jars filled and properly arranged for staining sections fastened 

 to slides. 



