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A NEW FIELD FOR THE MICROSCOPIST. 
By W.-SAVILLE KENT, F.L.S., F.Z.S., F.R.M.S. 
[PLATES III. AND IV.] 
I N no department of mechanical science, probably, during 
the last few years, has the march of progress been productive 
of more conspicuous and substantial fruits than in that one 
associated with the construction and perfection of the higher 
magnifying powers of the compound microscope. It is but a 
short while, indeed, since an amplification of some 500 linear 
diameters was about the utmost that could be safely relied 
upon by the microscopist for the accurate interpretation of 
independent minute organisms, or for investigating the ultimate 
structure of more highly complex tissues. Now, however, thanks 
to the mechanical and scientific skill of both English and 
foreign manufacturers specially devoted to this branch of 
optics, our range of vision among the atomic elements of this 
wondrous world has been extended to an almost incredible 
degree. A magnifying power of 2,000 or 3,000 diameters is 
in these days at the disposal of the merest tyro, while Messrs* 
Powell and Lealand, the opticians of this country to whom the 
palm of merit for the construction of object-glasses of the 
highest magnification is almost universally accorded, are able 
to produce a lens yielding with their deepest eyepiece an 
amplification of no less than 15,000 linear. To work successfully 
with a one-fiftieth inch objective and No. 5 eyepiece, the com- 
bination giving this marvellous magnification, or indeed to see 
anything with such a glass, belongs, as might be anticipated, to 
the professional expert only. A one- sixteenth inch objective, 
however, capable of yielding the more moderate but still con- 
siderably advanced amount of magnification previously named, 
is at the present date as accessible from a pecuniary point, and 
after a little practice is as convenient to work with as an 
ordinary one-quarter inch glass of the best construction. 
It would be a matter for congratulation if we could place on 
record side by side with this attestation to the mechanical 
perfection and improvements of our magnifying instruments, 
NEW SERIES, VOL. II. — NO. VI. I 
