WEIGHTS AND MEASURES. 



?y the quantity of motion it impresses on a 

 Dody; degrees of heat, by the expansion of 

 metals or other substances ; muscular strength, 

 by the resistance of a spring. See DYNAMO- 

 METER, STHEXRTH, THERMOMETER, &c. 



By measure, in an absolute sense, is under- 

 stood the unit, or standard, by which we mea- 

 sure extension. We have, therefore, measures 

 of length, of superficies, and of volume or ca- 

 pacity ; but, as the two latter may be deduced 

 in all cases from the former, it is only neces- 

 sary to establish a unit, or standard of length. 

 The choice of such a standard, and the differ- 

 ent multiples and parts of it taken for the uses 

 of society, form a metrical system, or system 

 of metrology. 



As no precise notion can be formed of the 

 magnitude 0* a line in any other way than by 

 comparing 1 ). with another line of a known 

 length, the necessity of having recourse, for 

 the interchange of ideas, to measures not en- 

 tirely arbitrary, but fixed by nature and intel- 

 ligible alike to all mankind, seem to have been 

 perceived in the earliest ages. Hence origi- 

 nated the foot, the cubit, or length of the arm 

 from the elbow to the tip of the middle finger; 

 the v.lmi, arm, or yard; the span ; the digit, or 

 finger; the palm; the fathom, or space from 

 the extremity of one hand to that of the other, 



WEIGHTS AND MEASURES. 



when they are both extended in opposite direc 

 tions ; the pace, the barley-corn, the hair's 

 breadth, and other denominations of measure 

 taken from parts of the human body, or from 

 natural objects, which, though not of an abso- 

 lute and invariable length, have a certain mean 

 value sufficiently definite to answer all the pur- 

 poses required in a rude state of society. But 

 as civilization advanced, the necessity of adopt- 

 ing more precise standards would be felt, and 

 the inadequacy of such measure as the foot, 

 the cubit, &c. (referred only to the human 

 body), to convey accurate notions, would be 

 rendered most apparent in their application to 

 itinerary measures, or the estimation of great 

 distances. 



Knglish System of Lineal Measures. The unit 

 of lineal measure in England is the yard, all 

 other denominations being either multiples, or 

 aliquot parts of the yard. The yard is divided 

 into 3 feet, and the foot subdivided into 12 

 inches. The multiples of the yard are the pole 

 or perch, the furlong, and the mile; 5^ yards 

 being a pole, 40 poles a furlong, and 8 furlongs 

 a mile. But the pole and furlong are now 

 scarcely ever used, itinerary distances being 

 reckoned in miles and yards. 



The relations of these different denomina- 

 tions are exhibited in the following table: 



Of the different measures of length used in 

 European countries, the foot is the most uni- 

 versally prevalent. We subjoin the relation 

 between the foot of different countries and the 

 English foot. 



English foot. 



Russian foot - - - - 1' 



Paris foot 1 065765 



Prussian and Danish foot - 1-029722 



Bavarian foot - 0"9575fil 



Hanoverian foot ... 0-958333 



Sax. >n foot .... 0-929118 



Austrian foot - 1-037128 

 See FOOT, LEAGUE, MILE, &c. 



Measures of Superficies. In square measure 

 the yard is subdivided, as in general measure, 

 into feet and inches; 144 square inches being 

 equal to a square foot, and 9 square feet to a 

 square yard. For land measure the multiples 

 of the yard are the pole, the rood, and the acre * 

 30^ (the square of 5^) square yards being a pole, 

 40 poles a rood, and 4 roods an acre. (See 

 ACRE.) Very large surfaces, as of whole coun- 

 tries, are expressed in square miles. 



The following are the relations of square 

 measure : 



Land is usually measured by a chain of 4 

 poles or 22 yards, which is divided into 100 

 links. Three chains in length and one in 

 breadth make an acre, which equals 169 square 

 perches, or 4840 square yards. 



Land Measure. 



Square, or Superficial Measure. 



144 square inches = 1 square foot. 



9 feet = 1 yard. 



30 yards = 1 rod. 



40 rods = 1 acre. 



640 acres = 1 mile. 



Measures of Volume. Solids are measured by 

 pubic yards, feet, and inches; 1728 cubic 

 inches making a cubic foot, and 2? cubic feet 

 a cubic yard. For all sorts of liquids, corn, 

 and other dry goods, the standard measure is 

 declared by the act of ] 824 to be the imperial 

 gallon, the capacity of which is determined im- 

 mediately by weight, and remotely by th 

 standard of length. See GALLOX. 



The parts of the gallon are quarts and pints, 

 2 pints being a quart, and 4 quarts a gallon, 



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