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POPULAR SCIENCE REVIEW. 
MICROSCOPY 
WENIIAM S BINOCULAR MICROSCOPE, 
HERE is no single instrument which has exercised such an impor- 
tant influence upon the advance of the sciences of anatomy and 
physiology, whether animal or vegetable, as the microscope. This invalua- 
ble aid to the otherwise limited power of the eye, has enabled us to peer 
inquisitively into the details of structure even of the minutest organisms, 
and to discover in them wonders and beauties, in the existence of which it 
would otherwise be hard to believe. The microscope is daily, under the 
eyes of numerous diligent observers, making discoveries of new facts, con- 
firming sound conclusions, and exploding fallacious theories ; and no 
scientific man can in this day expect to make either name or reputation, 
who does not call to his aid this powerful auxiliary. The physician, no 
less than the scientific zoologist and botanist, derives most important 
assistance from the microscope, and medicine can boast almost as great an 
advance as the collateral sciences. It is intended that the readers of the 
Popular Science Review shall be kept informed of the principal dis- 
coveries made from time to time by means of the microscope, and the 
Quarterly Retrospect of Microscopical Science will have for its object to 
keep the reader an courant with the ever rapidly accumulating knowledge 
and information upon such topics. 
Seneca, who wrote 64 a.c., tells us (Nat. Qusest. lib. i. c. 7) that 
“ letters, though minute and obscure, appear larger and clearer, when seen 
through a glass bubble filled with water and here the ancients stopped ; 
and although one would imagine that it would have been easy to make 
some sort of advance upon this phenomenon, yet not a step did they 
progress, although it is evident from Pliny (Nat. Hist. lib. xxxiv. c. 26), 
that they understood the art of grinding glass. 
But it appears that for seventeen centuries the glass bubble suggested to 
no one the possibility of improvement, nor can it be said with certain'y 
how the Dutchman, Drebbel, or the Italian, Fontana, to whom the inven- 
tion is indifferently ascribed, happily succeeded in conceiving and executing 
a microscope, about the year 1621. A great rarity, and costly withal, was 
the microscope of that day ; and we may safely infer that it was but a rude 
contrivance. In the middle of the same century, Van Leeuwenhoek 
improved upon it, and achieved a great reputation from his researches, the 
success of which arose from the care with which he polished his own lenses. 
The microscope used by this eminent anatomist consisted simply of a single 
lens, set between two plates of silver perforated with a small aperture. 
Compound microscopes contain lenses having distinct functions : one to 
receive the rays from the object and bring them to a focus, where an image 
is formed, which image is examined by another lens in the same way that 
the object itself is examined by the lens of a simple microscope. It is such 
an instrument as this which, originally poor and imperfect, has received 
for many years the utmost care and attention of the optician, with a view 
to its improvement and perfection ; with what results will presently appear. 
