104 REPORT— 1864. 



the metre, that, " in the measurement of a length hetween two points on 

 the surface of the earth, there is no advantage at all in proving the relation 

 of the measured distance to a quadi-ant of the meridian"*. Professor Miller, 

 of Cambridge, who quotes this remark, deems the error in the relation of the 

 metre to the quadrant of the meridian to be of no consequence ; and he 

 mentions another slight error in the metric system, discovered by recent 

 research, and relating to the density of water, which he gives in the following 

 words of Bessel t: — 



" The kilogramme (1000 grammes) is not exactly the weight of a cubic 

 decimetre of water. Many of the late weighings show that water at its maxi- 

 mum density has a diiferent density from that which was assumed by the 

 Erench philosophers who prepared the original standard of the kilogramme ; 

 but nobody wishes to alter the value of the gramme on that account." 



M. Chevalier stated to the Committee of the House of Commons on Weights 

 and Measui'es, in 1862, that, in calcidation, the metric system spares both 

 time and labour, exactly as a good machine would do for spinning or 

 weaving. 



The metric system is considered by Sir William Armstrong to be " the only 

 one which has any chance of becoming universal." 



Two important principles form the basis of the metric system. 



1. That the unit of linear measure, applied to matter, in its three forms of 

 extension, viz. length, breadth, and thickness, should be the standard of all 

 measures of length, sui'face, and solidity. 



2. That the cubic contents of the linear measure, in distilled water, at a 

 temperature of great contraction, should furnish at once the standard weight 

 and measure of capacity. 



Scientific advisers were summoned to the counsels of King Louis Philippe, 

 on his accession to the French throne, and that monarch has the credit of 

 having enforced the metric system in France. The opposition to the metric 

 system, among the French, had not arisen from the requirements of com- 

 merce ; the Department of the Bridges and High Roads and the officials of 

 the naval arsenals had, with the consent of the French government, aheady 

 adopted the metric system, and the new system came into general operation 

 in 1840. 



The Department of Commerce in France superintends the proper observance 

 of weights and measures. Standards made for the course of trade are very 

 numerous. 



" If you have been walking about Paris," says M. ChevaHer, " you may 

 have seen the metre in the streets, fixed in the wall of many a pubhc build- 

 ing. It is made by public authority. Any buyer, who is afraid that he has 

 been cheated, can go to some street at a short distance, and there he finds the 

 measurement of the metre, fixed by authority for the use of the people : besides, 

 he has a process more simple, to know whether he has been dealt with fairly ; 

 he has his own metre in his pocket." 



Verifiers of weights and measures are appointed in every district (arron- 

 dissement) of France, and each verifier has his own set of these instruments. 

 Measures are made very cheap in Pai'is : balances furnished with smaU weights 

 may be purchased at a small expense ; and in the larger weights, the principal 

 expense is in the metal. 



* Eeport of a Committee of the House of Commons on Weights and Measures, p. 109, 

 1862. 



t From the ' Populare Vorlesungen,' by Professor Bessel, published in 1848, soon 

 after his death. 



