458 COMPARISON OF THE VARIOUS MEASURES OF LENGTH 



wissench. Klasse, vol. xliv.) Struve's value has been adopted in computing the 

 tables in this edition. 



6. Tlie Prussian Foot is marked on a standard iron bar, 3 feet long, made by Pistor 

 in Berlin ; it is a standard at the temperature of 18° Reaumur. The length of the 

 Prussian foot was declaied by law to be = 139.13 lines of the toise du Perou. 



7. Spain and the old Spanish Colonies of America. The French metrical 

 system of weights and measures was introduced into Spain by law in July, 1849 ; 

 but its introduction was only finished in 1859. The old measures, however, con- 

 tinued to have a considerable local significance. Among the different values assigned 

 to them the most important are those of the Castilian Vara, or Vara de Burgos, 

 and of the Castilian foot, the relation of which to the metre is given officially in the 

 Anuario de la Direccion de Hidrograjia, Madrid, 18G3, as I'oUows : 



1 Castilian foot = 0.278635 metre ; hence 



1 Castilian vara =0.8359050 metre 



1 Castilian foot =0.9141732 English foot. 



These values have been used in computing the tables in this fourth edition, in 

 preference to the older ones, from which the tables in the previous editions were 

 derived. 



In the late Spanish Colonies of Mexico and South America the measures of the 

 mother country continued to be in use after their separation from it. But owing, 

 no doubt, to the imperfection of local standards, considerable divergences were 

 found to exist, which caused no little confusion in the practical use of these mea- 

 sures. To obviate this inconvenience some of the States, as Mexico in 1862, Chile 

 already in 1848, decreed the introduction of the French metric system. But as in 

 practice the people continued to use the old measures, most of the States found it 

 necessary to fix a legal value for the vara in relation to the metre. Thus Mexico 

 determined by law, in 1845, the legal value of the Mexican vara to be 



1 vara = 0.838 metre ; hence 



1 Mexican foot = 0.2793333 ' 



1 Mexican foot = 0.9164645 English foot. 



Guatemala, San Salvador, Honduras, Nicaragua, Costa Rica use the Mexican vara 

 and foot. 



According to Col. T. Ondarza, one of the authors of the official map of Bolivia, 

 the Bolivian government has declared the value of the Spanish vara to be in the 

 ratio of 100 metres =118 varas. This value was adopted by him in publishing 

 his altitudes. Thus 



1 Bolivian vara = 1.18 metre; hence 



1 Bolivian foot = 0.28248.T9 " 



1 Bolivian foot = 0.92G80776 English foot. ^ 



Chile and Peru use the same value of the vara and foot as Bolivia. Venezuela, 

 New Granada, and Ecuador have adopted a value of the vara very nearly equal to 

 the old Castilian, viz. : — 



1 vara = 0.836 metre. 

 1 foot = 0.278667 '^ 

 E 12 



