88 



relation to the length of the pendulum, vibrating seconds of mean 

 time, in a vacuum, at the level of the sea ; and that the pound shall 

 be restored by taking the weight which bears a certain proportion to 

 the weight of a cubic inch of water weighed in a certain manner. 

 The Commissioners, however, in their Report dated December 21, 

 1841, decline to recommend the adoption of these provisions for the 

 following reasons : " Since the passing of the said Act it has been 

 ascertained that several elements of reduction of the pendulum expe- 

 riment therein referred to are doubtful or erroneous. It is evident, 

 therefore, that the course prescribed by the Act would not necessarily 

 reproduce the length of the original yard. It appears also that the 

 determination of the weight of a cubic inch of water is yet doubtful 

 (the greatest difference between the best English, French, Austrian, 

 Swedish and Russian determinations being about - t ^ 6 of the 

 whole weight, whereas the mere operation of weighing may be 

 performed to the accuracy of ^^ of the whole weight). Several 

 measures, however, exist, which were most carefully compared with 

 the former standard yard ; and several metallic weights exist which 

 were most accurately compared with the former standard pound ; 

 and by the use of these the values of the original standards can be 

 respectively restored without sensible error. And we are fully per- 

 suaded that, with reasonable precautions, it will always be possible 

 to provide for the accurate restoration of standards by means of 

 material copies which have been carefully compared with them, 

 more securely than by experiments referring to natural constants." 



At the end of the Travaux de la Commission pour fixer les Me- 

 sures et les Poids de 1'Empire de Russie, Professor Kupffer has col- 

 lected the results of observations made in France, England, Sweden, 

 Austria and Russia for finding the weight of a given volume of 

 water. The resulting values of the weight of an English cubic inch 

 of water in a vacuum at 62 Fahr., expressed in doli, of which 

 22504-86 make a kilogramme, are as follows : 



French observations 368-365 



English observations 368-542 



Swedish observations 368-474 



Austrian observations 368*237 



Russian observations. . . 368-361 



