The Microscope. 85 



I have no ideal series to suggest, but I have a series that I am 

 «ure the reader, especially if he be about to buy a microscope, 

 will find of great service, and one that will remain good to the 

 •end, and will enable him to do considerable original investiga- 

 tion, if he so desire. In mentioning the objectives, I have no 

 •other purpose than the one that I have attempted to make prom- 

 inent. The dealers whose excellent work is to be mentioned are 

 welcome to the advertisement. It should be a greater one if I 

 could make it so. And the reader may rest assured that any 

 coincidence that he may notice between the names of the opti- 

 cians in this list and in the advertising pages of the magazine, 

 is a coincidence only. Every one of these objectives was bought, 

 and had been used for several years before I had the least thought 

 that I should ever be the Editor of The Microscope. If the 

 accomplished gentlemen to be named shall sell more of their 

 objectives by reason of this notice, no one will be better pleased 

 than I. Their work is fine ; it merits every commendation, and 

 I am happy that I can give it. I can therefore recommend the 

 following as a list of good objectives that I am familiar with, and 

 that the reader will find satisfactory in every particular, and with 

 which he may do original work. If he does not care to perform 

 that nerve-wearing labor, then these lenses will give him glimpses 

 into the secrets of Nature that no others of a lower grade could 

 ■ever show him. 



For a two inch, which is very useful at times, take Quean and 

 Co's ; for a lower power, that is hardly needed except as a luxury, 

 Zeiss's variable A* is superb ; this may be varied from a three to a 

 iive inch. For the one inch by all means select Spencer's, of 33° 

 aperture. Beyond this nothing will be needed, except as a lux- 

 ury that may be dispensed with, until the ^ is reached. This 

 should be Gundlach's, Class D, 135° aperture ; and the highest 

 power needed by any one, unless he is going into delicate investi- 

 gations, is the ^, that should be the best made and homogeneous 

 immersion. For this lens take Messrs Bausch and Lomb's. It 

 is a superb thing and worth every dollar that it costs. Should 

 the reader desire to go higher, as he probably will not, then he 

 may confidently select Spencer's homogenous immersion to- 

 This is magnificent. It is the equal of any thing made •by any 

 optician any where in the world, not excepting the apochro- 

 anatics of Zeiss. But with the ^ the microscopist has all that he 



