Introduction. 



giving only the ordinary methods used by the author in 

 his own Laboratory. 



When all these methods have been thoroughly worked 

 out, the student will find himself competent to try any 

 of the various processes mentioned in larger works, and 

 to judge of their utility. 



Many men on reading the different hardening, cut- 

 ting, staining, and mounting processes which any tissue 

 has to undergo before it can be examined with the 

 microscope, will be inclined to think it very tedious 

 work. It is, however, a mere matter of routine, and 

 when once this routine is established, the whole thing 

 is comparatively simple. It takes very little time to 

 change the hardening fluid, and if the student gets into 

 the habit of looking over the bottles on the shelf every 

 morning, where he keeps those tissues in the process of 

 hardening, a glance at the labels will show those re- 

 quiring a change. When the sections are mounted and 

 examined under the microscope, he will find himself 

 amply repaid for all his trouble if he has faithfully 

 carried out the different processes in every detail. 



It is always better to have one or two shelves devoted 

 to those preparations which require changing ; and those 

 such as chromic acid, which require fresh fluid often, 

 should be kept by themselves. Each bottle should be 

 labelled, and the tissue, date, and hardening fluid, 

 clearly written on the label. Every morning this 

 shelf should be examined, and those requiring it, 

 changed; the date being each time written on the 

 label, so that it may be seen at a glance how long the 

 tissue has been in the fluid, and whether the hardening 



