THE METRIC SYSTEM. 



io-centimeter rule. The upper edge is in millimeters, the lower in centimeters and half- 

 centimeters. 



UNITS. THE MOST COMMONLY USKD DIVISIONS AND MULTIPLES. 



Centimeter (cm), i/ioo meter; Millimeter (mm), 



THE METER, for 



i/iooo meter; Micron (//), i/iooo millimeter. The 



micron is the unit in micrometry. 



Kilometer, 100 meters; used in measuring roads and other 



long distances. 



THF GRAM for ( Milli S ram ( ra g)> V IOO g ram - 



WEIGHT 1 Kil S ram i I00 grams, used for ordinary masses, like 



( groceries, etc. 



THE LITER, for j Cubic Centimeter (cc), i/iooo liter. This is more 

 CAPACITY. ... ( common than the correct form, Milliliter. 

 Divisions of the units are indicated by Latin prefixes: deci, i/io; centi, 



I/ioo; milli, i/iooo. 



Multiples are designated by Greek prefixes: deka, 10 times; hecto, 100 



times; kilo, 1000 times; myria, 10,000 times. 



TABLE OF METRIC AND ENGLISH MEASURES. 



METER = 100 centimeters, 1000 millimeters, 1,000,000 microns, 39.3704 

 inches. 



Millimeter (mm) = looo microns, I /io millimeter, i/iooo meter, 1/25 inch, 

 approximately. 



MICRON (fi) (unit of measure in micrometry ) i/iooo mm, i/ioooooo me- 

 ter (0.000039 inch), 1/25000 inch, approximately. 



Inch (in.) = 25.399772 mm (25.4 mm, approx.). 



LITER = 1000 milliliters or 1000 cubic centimeters, I quart (approx.). 



Cubic centimeter (cc or cctm) = i/iooo liter. 



Fluid ounce (8 fluidrachms) = 29.578 cc (30 cc, approx.). 



GRAM 15.432 grains. 



Kilogram (kilo) = 2.204 avoirdupois pounds (2\ pounds, approx.). 



Ounce Avoirdupois (437^ grains) = 28.349 grams ) (30 grams, 



Ounce Troy or Apothecaries' (480 grains) = 31. 103 grams ) approx. ). 



TEMPERATURE. 



To change Centigrade to Fahrenheit: (C. X f) +32 = F. For example, to 

 find the equivalent of 10 Centigrade, C. = 10, (10 X f ) + Z 2 = 5 F - 



To change Fahrenheit to Centigrade: (F. 32) X f = C. For example,to 

 reduce 50 Fahrenheit to Centigrade, F. = 50, and (50 32) X f = 10 C. ; 

 or - 40 Fahrenheit to Centigrade, F. = 40, (- 40- 32) = - 72, 



A = _ 40 C. 

 From "The Microscope" (by S. ff. Gage) by permission. 



