THE MICROSCOPE. 
473 
Birmingham, who is hound by agreement with the Society of 
Arts to keep the instrument always in stock, and supply any 
purchaser at once. It has two eye-pieces and two achromatic 
objectives, varying in power from 25 to 200 linear, a condenser 
on a separate stand, coarse and fine adjustment, stage-forceps, 
and live-box ; and the whole, in a mahogany case, may be pur- 
chased for three guineas. 
Finally, for further information upon the subject of the 
optical and mechanical principles of the microscope, manipula- 
tion, apparatus, collection and mounting of objects ; and for an 
elaborate illustrated description of the microscopic forms of 
animal and vegetable life, we cannot do better than recommend. 
Dr. Carpenter’s work on “The Microscope and its Revelations ” 
(price twelve shillings and sixpence) in Churchill’s series of 
scientific manuals.* 
* Useful little French microscopes for beginners with limited means may 
be purchased for ten and sixpence (walnut-wood case included) ; and for such 
also Dr. Lankestefis little work, “ Half-hours with the Microscope,” illus- 
trated by Tuffen West, F.L.S., will be found serviceable. — Ed. 
