292 
NOTES AND MEMORANDA. 
behind, letting it stand for some hours each time to settle, in order 
to be sure of not losing the smallest particle of it in pouring off 
the water. Those w r ho follow this method exactly cannot fail to 
succeed. The object may then be mounted with Canada balsam, or 
in any other suitable medium ; and steadily and closely watching it 
under the microscope, they will not be long before they see some 
valves of diatoms, entire or broken. 
Examination of the Animal Tissues for Starch — Mr. T. Taylor, 
in the monthly Report of the Department of Agriculture to the 
American Minister, makes some very astonishing statements. Those 
who have been accustomed to examine the human tissues with powers 
of from 300 to 800 diameters will be somewhat surprised at the 
following assertion: — If about a cubic inch of liver, spleen, heart, 
brain or muscle of the higher animals be immersed in two fluid- 
ounces of caustic potash about twenty-four hours, at a temperature of 
about 80° Fahrenheit, it will dissolve completely. On the addition 
of acetic acid in excess, the potash will be neutralized, and a flocculent 
precipitate will fall, which, by ordinary filtration, may be separated 
from the liquid. Remove the filtrant by means of a sable-hair pencil, 
taking care not to remove any of the fibre of the paper with the 
animal matter. Place a- small portion of the filtrant on a capsule, and 
add to it a drop of concentrated sulphuric acid, followed by one of the 
tincture of iodine. Then place a portion of the composition on a 
microscopic slide, covering it with a disk in the usual manner, and 
examine it with a power of about 100 diameters Under these con- 
ditions blue granules of animal starch and structural cellulose will 
sometimes be seen, combined with amber-coloured albuminous matter. 
Frequently starch and cellulose, although present, are not seen, but 
by subjecting the composition to friction, and adding a little more 
sulphuric acid and iodine, well-defined blue-coloured structural forms 
become apparent. 
An Instrument for Cleaning Thin Covering Glass has been thus 
described by Mr. W. W. Jones to the Quekett Club. The paper is 
fully published in the ‘Journal of the Quekett Club.’ The following 
is the account of the instrument : — It consists of a small tube of brass 
or steel, of about an inch in diameter and the same in height, into 
which fits loosely a weighted plug. To the lower end of this plug is 
cemented a piece of chamois leather. Another piece of leather is 
stretched upon a flat piece of wood or plate glass to form a pad, which 
completes the apparatus. The mode of using it is this. You place 
the tube on the pad, breathe on the glass, drop it into the tube, put 
in the plug, and then holding the tube well down on the pad you can 
rub as much as you like with perfect safety, the weight of the plug 
giving sufficient pressure. With this simple arrangement you will 
find it almost as difficult to break the glass as many have hitherto 
found it easy. 
