26 THE AMERICAN MONTHLY [Jan 



Our list of foreig-n correspondents has larg-ely increased 

 and we now have friends all over the world in nearly every 

 nook and corner. We trust our home lists will corres- 

 ponding-ly increase during- the new year. To all we extend 

 a hearty g-reeting-. 



LETTERS TO THE EDITOR. 



GATES' DOUBLE MICROSCOPE. 



Unless he can make opposite defects in each correct each 

 other I do not see what he can gain. I tried a somewhat 

 similar experiment, with the telescope or spyg-lass in my 

 schoolboy da3^s, but it did not take me long- to find out that 

 mete magnification without a corresponding- improvement 

 in deffinition and resolution was worthless. I think it 

 possible that a double objective mig-ht be made so that de- 

 fects of one system mig-ht be corrected by the opposite 

 defects of the other, and in this way a much g-reater work- 

 ing- distance be obtained with a g-reater depth of focus and 

 eqfial resolution. If my health was better I should try 

 some experiments in this line myself. — Wm. A. Terry. 



V^ill Report own V7ork Later. — "I have corresponded 

 with Mr. Gates as to his Double-Microscope. I have 

 thoug-ht favorably of it notwithstanding- Dr. Stokes' stric- 

 tures, especially as I made some experiments thirty 

 years ag-o on it. I got a l-5th and a 1-Sth in the eye-piece 

 and a l-15th and a l-5th in the eye-piece. That was as hig-h 

 as I could g-o. I had not hig-her objectives to try, and only 

 sunlig-ht. The definition was gfood cnoug-h. I intended 

 to publish a paper on the subject — and still intend to do so 

 when I can g-et the time. But I must submit my paper to 

 both g-entlemen. The Journal shall hear from me on it 

 soon." — Arthur M. Edwards, M. D. 



Get Actual Results Properly Certified. — "I am too busy 

 to write an article on Dr. Elmer Gates' tandem micro- 

 scopes. Would it not be much better to get some one 

 rig-ht on the ground who knows Dr. Gates and can see his 

 laboratory, etc. I would suggest Dr. Frank Baker. Every 



