148 
ELEMENTARY CHEMICAL MICROSCOPY 
millimeters of the drawn-out end are slightly roughened with a 
piece of fine carborundum or emery cloth, or ground on a wheel, 
Fig. 8i. Drawn-out Glass Rod and Platinum Wire for handling Reagents. 
it will be found that both liquids and solids are more easily trans¬ 
ferred and handled than if the glass be smooth. Slightly breath¬ 
ing on the end of the rod, or touching it to one’s fingers before 
bringing it in contact with the reagent will cause tiny fragments 
of dry powders to cling to the rod long enough to permit all usual 
transfers. Similarly, roughening the end of the platinum wire 
improves its carrying power. Rods and wires roughened, neces¬ 
sarily require more care in cleaning after use than when polished. 
Tiny pipettes may be employed for transferring solutions or 
liquid reagents, but are so difficult to keep thoroughly clean that 
it is wiser to employ short lengths of tubing of capillary bore made 
by drawing out odds and ends of glass tubing. Such substitutes 
for pipettes draw up the solutions to which they are touched by 
capillarity — the liquid can easily be expelled by gently blowing 
into one end of the tube, the other end being held against an 
object slide. After transferring the liquid, the capillary tube is 
thrown away. 
Spatulas. — Larger amounts of dry reagents than can con¬ 
veniently be handled by the glass rods or platinum wires may be 
transferred by means of small platinum spatulas. Fig. 82, made 
P'lG. 82. Platinum Spatula for Microchemical Analysis. (Full size.) 
from a piece of platinum wire about one millimeter in diameter 
and 80 to 85 millimeters long, one end of which is hammered out 
flat on a polished steel surface until it becomes a little over 3 
millimeters wide and the flattened surface about 10 millimeters 
long. The blade thus prepared is shaped and smoothed with a 
fine file and polished. The end of the handle is given a gentle 
