Weight (redirected from molecular weight)

WEIGHT. A quality in natural bodies, by which they tend towards the centre of the earth.
     2. Under the article Measure, (q.v.) it is said that by the constitution congress possesses the power "to fix the standard of weights and measures," and that this power has not been exercised.
     3. The weights now generally used in the United States, are the same as those of England; they are of two kinds:

                 1. AVOIRDUPOIS WEIGHT. 
  1st. Used in almost all commercial transactions, and in the common 
dealings of life. 
 27 1/3 1/2 grains  =    1 dram 
 16 drams           =    1 ounce 
 16 ounces          =    1 pound, (lb.) 
 28 pounds          =    1 quarter, (qr.) 
 4 quarters         =    1 hundred weight, (cwt.) 
 20 hundred weight  =    1 ton. 
 
 2d. Used for meat and fish. 
 8 pounds           =    1 stone 
 
 3d. Used in the wool trade. 

                                     Cwt. qr.  lb. 
 7 pounds           =    1 clove 14 pounds           =    1 stone  =   0    
0   14 
 2 stones           =    1 tod    =   0    1    0 
 6 1/2 tods         =    1 wey    =   1    2   14 
 2 weys             =    1 sack   =   3    1    0 12 sacks            =    1 
last   =  39    0    0 
 
 4th. Used for butter and cheese. 
 8 pounds           =    1 clove 
 56 pounds          =    1 firkin. 
 

                     2. TROY WEIGHT. 
 24 grams           =    1 pennyweight 
 20 pennyweights    =    1 ounce 
 12 ounces          =    1 pound. 

     4. These are the denominations of troy weight, when used for weighing gold, silver and precious stones, except diamonds. Troy weight is also used by apothecaries in compounding medicines; and by them the ounce is divided into eight drams, and the drain into three scruples, so that the latter is equal to twenty grains. For scientific purposes, the grain only is used, and sets of weights are constructed in decimal progression, from 10,000 grains downward to one-hundredth of a grain. The caret, used for weighing diamonds, is three and one-sixth grains.
     5. A short account of the French weights and measures is given under the article Measure.