SOLID ELEMENTS, AND THEIR PERIODIC RELATIONS. 



61 



curves for each single metal. This method of calculation brought essen- 

 tially the same results. 



We are greatly indebted to Mr. F. N. Brink for his kindness in making 

 determinations Nos. 29 to 31 inclusive, as well as Nos. 34 to 37 inclusive, 

 and for his assistance in independently recalculating the results. There 

 are included in the table also repetitions of two of his determinations of 

 copper and iron (13 and 27) given in the paper immediately preceding 

 this one. 



The close agreement of successive determinations, and especially the 

 consistent verdict of the independent results of the two different experi- 

 menters (except in the single case of chromium), furnish good reasons 

 for trust in the approximate accuracy of the results. The series is never- 

 theless not to be regarded as the final word upon the subject, but rather 

 as a preliminary attempt to solve an experimental problem of no small 

 difficult)'. It bears the same relation to an ideal research on this subject 

 that a sketch bears to a finished picture. 



Data concerning the compressibilities of twenty-one metals. 



1- The first sample of paraffin oil was used here. In all the other experiments except Nos. 28 and 29 water was used. 



