USEFUL TABLES AND FORMULAE. 659 



Weights and Measures. 

 Troy Weight— 



24 grains 1 pennyweight. 



20 pennyweights 1 ounce. 



12 ounces 1 pound. 



Apothecaries' Weight — 



20 grains 1 scruple. 



3 scruples 1 drachm. 



8 drachms 1 ounce. 



12 ounces 1 pound. 



Avoirdupois Weight — 



27.34 grains 1 drachm. 



16 drachms 1 ounce. 



16 ounces 1 pound. 



Long Measure — 



12 inches 1 foot. 



3 feet 1 yard. 



5| yards 1 rod, pole or perch. 



40 rods 1 furlong. 



8 furlongs 1 statute or land mile. 



3 miles 1 league. 



Square or Land Measure — 



144 square inches 1 square foot. 



9 square feet 1 square yard. 



30J square yards 1 square rod. 



40 square rods 1 rood. 



4 roods 1 acre. 



640 acres 1 square mile. 



Liquid Measure — 



4 gills 1 pint — 28.875 cubic inches. 



2 pints 1 quart — 57.75 cubic inches. 



4 quarts 1 gallon— 231 cubic inches. 



63 gallons 1 hogshead. 



2 hogsheads 1 pipe or butt. 



2 pipes 1 tun. 



Dry Measure — 



2 pints 1 quart. 



4 quarts 1 gallon. 



2 gallons 1 peck. 



4 pecks 1 struck bushel. 



