ON HIGH POWERS, AND A STEADY MICROSCOPE. 21 
played. By adopting the plan just described all this annoy- 
ance and uncertainty will be obviated. If an object happens 
to be in an awkward or unfavorable position the cover can 
be raised, and all set right with the greatest ease. Being 
clean, simple, and easy, this method offers every encourage- 
ment to students to mount their own preparations. Nothing 
so much deters from mounting microscopic preparations as 
the idea that so much trouble will be incurred in getting all 
ready before anything can be done. I must not omit to 
mention that, with proper care, there need be no cleaning off 
of surplus balsam, for it is so easy to calculate the exact 
quantity required for a given object, and this can be regu- 
lated with such nicety that only as much need be dropped 
on the preparation as will be just sufficient for the purpose. 
A few Remarks on the following Extracts from Papers by 
Cuartes Brooke, Esq., President of the Microscopical 
Society of London, and by the Enitor of the ‘ Intellectual 
Observer. Also on a Parur by J. J. Prumer, Esq., en- 
litled “A few Words on the Choice of a Microscope,” to be 
found at page 153 of the ‘ Quarterly Journal of Microsco- 
pteal Science’ for July, 1864. By E. G. Loss. 
Extract I. 
From the ‘ Jurors’ Report of the International Exhibition’ for 
1862. Class 138, page 21. 
“ No objective yet manufactured for sale at all rivals in its 
power of development the =th of Messrs. Powell and Lea- 
land. These able artists have hkewise been very successful 
in the construction of the deepest previously acknowledged 
powers, namely, those of th and -!;th inch focus; in these 
objectives excessive angular aperture has been judiciously 
sacrificed to more comprehensive and practical utility.” 
Extract II. 
From the President’s Address, page 74 of the ‘ Quarterly 
Journal of Microscopical Science, April, 1864. 
«‘T must in conclusion remark, that I have not hitherto 
succeeded in developing any point of organic structure with 
