256 
POPULAR SCIENCE REVIEW. 
the unwise selection of a season adopted by the Microscopical Society for 
aAvarding its j)rize medals. 
A new Form of Mounting Table has been described by T. G. Stokes, who 
objects to Mr. Goddard’s contrivance, upon the ground that there is no 
provision for regulating the temperature, so as to prevent its rising to the 
boiling point of Canada balsam. He has for some time employed a water- 
bath of tin or zinc, 14 in. by 3^ in., aiifl 3^ in. deep, wuth a ledge running 
round the top to prevent the slides from slipping. If a cover of cardboard 
be j)laced on this to keep off the dust, and the orifice through which the 
water is introduced left oj>en, the apparatus, with the slides on it, may be 
left to itself for any reasonable length of time over any source of heat. — See 
the Quarterly J ournal of Microscoincal Science, December. 
Use of Dyes in Microscopical Investigations. — Some obser\^ations of the 
utmost import have recently been made by Mr. Walter Abbey, M.E.C.S., 
upon this matter. This gentleman, who differs in ojDinion from the con- 
clusions at which Dr. Beale has arrived, turned his attention to the study of 
colours which attract certain portions of tissues and these only. In 
searching for new dyes, as substitutes for additions to carmine, which is now' 
so much employed, he has discovered a blue tinting solution allied to the 
aniline compounds, which “ has intense and splendid colourmg power, and 
is even more brilliant by artificial light than by daylight. It is also freel}' 
soluble in water ; thus refuting Dr. Beale’s explanation of the limited dyeing 
power of carmine, which he attributes to the acid reaction of the ‘ germinal 
matter’ upon the alkaline solution of the dye.” Mr. Abbey, by experimenting 
with various colouring matters, has been enabled to separate the secondary 
layers of the vegetable cell from both the cell-wall arid the nucleus. He 
enumerates the following conclusions, which differ very materially from 
those of Dr. Beale : — 
1. The germinal matter, so called, consists of tw'o parts — the one dyed 
by carmine, the other not so. 
2. It is not possible by means of tinting agents to demonstrate the gradual 
transition of living matter into dead matter. 
3. The varying tints of the dyed nucleus are due to the greater or less 
dispersion of the coloured molecules through the uncoloured substance, their 
close aggregation forming the nucleolus. 
4. The uncoloured portion of the germinal matter is the product of the 
coloured portion. 
5. Nutrition is least active in the most deeply-coloured part of the 
“ germinal matter.” 
Mr. Abbey suggests the employment of a new set of expressions, which, 
however, we regard as being more ill-timed than those of Dr. Beale. We do 
not bind ourselves to a faith in the doctrines of either, and we hold that the 
question of development of tissues is even yet in an unworked condition. — 
See for Mr. Abbey’s paper, the Microscopical Journal, vol. IV., p. 269. 
A Cheap Form of Dissecting Microscope, which is represented in the 
annexed woodcut, has been constructed by Messrs. Baker, opticians, of 
Holborn. This instrument, which commends itself to all working histologists, 
consists of a solid circular foot of brass, from the border of which arises a 
firm leg, supporting the stage — which is of ample dimensions — and the body. 
