Weight Measure and Specific Gravity. 



What is weight? Weight is the difference between 

 the attraction of the earth and that of surrounding 

 bodies for bodies n the surface of the earth. 



What is meant by Volume? Volume is the space 

 occupied by a certain, amount of matter. 



What systems of Measures are used in Pharmacy? 

 Apothecaries' or Wine Measure, Imperial or British, 

 and the Metric system. 



What standards are used upon which to base the 

 system of Weights? The Grain and the Metre. 



What system of weights used in Pharmacy are 

 based on the Grain? The Troy or Apothecaries' 

 system and the Avoirdupois system. 



State the number of grains in an ounce, Avoirdu- 

 pois and Apothecaries'. 



437.5 Avoirdupois. 480 Apothecaries.' 



Are the grains of each the same? Yes. 



State the denominations of Troy or Apothecaries 

 and Avoirdupois Weights. 



Troy or Apothecaries' Weight: 20 grains, I scru- 

 ple; 3 scruples, I drachm; 8 drachms, I ounce; 12 

 ounces, I pound. 



Avoirdupois Weight: 437^ grains, I ounce; 16 

 ounces, I pound. 



What is the difference in grains between the 

 Avoirdupois and Troy pound? Avoirdupois pound, 

 7,000 grains; Troy pound, 5.760. Avoirdupois 

 pound, 1,240 grains heavier. 



What is the difference in grains between the Troy 

 and Avoirdupois ounce? Avoirdupois ounce, 437^2 

 grains; Troy ounce, 480 grains, Troy ounce, 42^ 

 grains heavier. 



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