362 HOW TO SEE WITH THE MICROSCOPE. 



eous request. My position had been placed fairly before the 

 public for years, and I was. for the nonce, content in maintain- 

 ing silence, feeling assured that when attention should be 

 thoroughly aroused as to the claims of high-angled glasses, that 

 I would be better understood. I think I can to-day safely 

 assert that my expectations have been realized, and to a greater 

 extent than I had any reason to anticipate. 



Prof. Hitchcock has done me the honor of an extended reply 

 in the September number of this journal. It is noticeable that 

 he still preserves the same courteous bearing which character- 

 ized his previous paper ; indeed he pays me a compliment ("We 

 have his plain statements, and we accept," etc., p. 110). All 

 this, as an index of his good nature, is very acceptable. 



Nevertheless, be it remembered that it has been no part of mv 

 purpose to obtain acceptance per se of my positions. On the 

 contrary it has been my earnest endeavor to excite attention,. 

 and to induce my readers to experiment for themselves. Hence 

 the results of my tedious and protracted experience with the 

 duplex lenses were printed in forcible terms (heterodox as they 

 must have seemed to many), allowing no loop-hole for retraction 

 or qualification on my part. Hence it was, too, that I requested 

 Prof. Hitchcock to repeat some of my experiments ; Prof. II. 

 is compelled to decline, because he has not the objectives at 

 command. This I sincerely regret. 



Premising that my time is fully occupied, and that it will be 

 impossible to reply directly to Piof. Hitchcock's last, and inter- 

 esting paper, I proceed to offer a few thoughts suggested by -ne 

 same. 



First, what, in common parlance, constitutes a high-angled 

 objective ? I think I understand Prof. Hitchcock perhaps 

 not let us see. It may be that in arriving at a mutual under- 

 standing on this point, we may get, generally, nearer coinci- 

 dence. Now, most observers associate with the term " high- 

 angled objectives," some great display of figures. Thus, 175 r 

 178, or the " impossible " 180. Others might go still further, 

 turning the 180 corner, and thus revel in the" balsam angles* 

 say, up to 100 or higher. Such are not exactly my own notions. 



I regard as high-angled, all objectives from a 4-inch to a 



