;;i54 The Mickoscope. 



of interstitial imbedding and fixing the section immediately on the 

 slide; for he makes the point against thin sections that they are man- 

 ipulated with difl&culty, and there is loss of time in spreading them 

 on the slide ( italics my own) ; hence, it is not surprising that the 

 cell-elements could not be preserved, and the object of the examina- 

 tion secured. 



Elsewhere, * I have attempted to tell, in as precise language as I 

 could express, the successive steps, as I am in the habit of employ- 

 ing them, of hardening, imbedding, cutting, staining and mounting 

 tissues; but am none the less sensible of my failure to impart all the 

 knowledge which experience has given me. Language, however 

 simple and precise, cannot convey technical skill in microscopy any 

 more successfully than it can tell the difference between your voice 

 and my own. The how must be seen to be learned without stum- 

 bling and many discouragements ; and hence, I should be willing to 

 promise the gift of more knowledge in a few hours' time to the 

 student at my work-table, than I could impart by writing in as many 

 days. 



Impressed with this truth, I begged the American Society of 

 Microscopists at the Pittsburg meeting, last year, to adopt a rule 

 appropriating a part of each day for a working demonstration, and 

 henceforth, I trust there will be greater interest in the meetings 

 and better progress in practical work, for it is safe to say that 

 seven-tenths of all those who respond to the annual convocation attend 

 the meeting for the special purpose of learning something of the 

 how to work— not to spend three days and a half out of the four 

 in listening to the reading of cold facts which will keep, like good 

 wine, in all sorts of weather and may be better studied in the 

 volume of transactions than understood on the floor of the general 

 sessions. 



Presuming upon the origin of the new rule establishing a 

 daily working session, and in view of the fact that its usefulness, 

 soon to be put to practical test at the Columbus meeting, may mis- 

 carry from a failure to select the best method of putting it into 

 operation, I offer the following gratuitous suggestions: 



First. — But one thing or subject at a time, and a special 

 demonstrator appointed for each department. For example, the 

 first hour should be occupied in showing the best methods of pre- 

 paring objects and materials for the microtome. This will include 

 the processes of hardening and imbedding different tissues. To 

 make the lesson profitable in the highest degree, the fresh specimen 



* How to work with the Bausch & Lomb microtome. 



