The Philippine Journal of Science, C. Botany. 
Vol. XIII, No. 4, July, 1918. 
SOME MICROTECHNICAL METHODS AND DEVICES 
By Walter R. Shaw 
{From the Department of Botany, University of the Philippines, Manila) 
FIVE TEXT FIGURES 
contents 
1. Ocular micrometers used as stage micrometers. 
2. The square-ruled micrometer used as a position indicator. 
3. The square-ruled micrometer for drawing to scale. 
4. Capillary glass rods for cover-glass supports. 
5. Autographic records on micrographic negatives. 
6. A method of recording magnification on micrographic negatives. 
7. Concentration of glycerin hastened by the vacuum pump. 
8. A method for making sealed glycerin mounts. 
9. The Osterhout mounting method adapted to Volvocaceae. 
10. A plankton net for larger organisms. 
11. Washing devices for small objects. 
12. Methods of estimating the number of cells in spheroidal surfaces. 
During several years of teaching botany and pharmacognosy, 
and collecting and preparing material for a study of the Volvoca- 
ceae of the vicinity of Manila, it has been found expedient to 
employ modifications of the methods laid down in the various 
laboratory handbooks. For the most part these modifications, 
made to meet requirements of the work in hand and local con- 
ditions, have originated in suggestions obtained during many 
years from many sources which it would now be difficult, if 
not impossible, to trace. The methods and devices here pre- 
sented have served useful purposes for the writer and his stud- 
ents in the past and are here published that they may be available 
for others in the future. 
OCULAR MICROMETERS USED AS STAGE MICROMETERS 
In an instruction laboratory in which each compound micro- 
scope is furnished with a linear and a square-ruled micrometer 
disk, each of these scales may be used as a stage micrometer 
for determining the value of the intervals of the other used 
as an ocular micrometer. The disk to serve as the stage micro- 
meter is easily affixed to a clean slide with a capillary film of 
water. By this means I am enabled to give simultaneously to 
all the students of a class exercises in the determination of the 
micrometer scale values without the expense of supplying a 
stage micrometer for each student. 
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