188 MEMOIR OF THE LATE PROF. E. HODGKINSONj F.R.S. 



sought the restoration of his exhausted faculties by a tour 

 on the continent of Europe. 



His labours for this Commission are published in the 

 Report, and comprise 114 closely printed pages. The high 

 importance of these labours may be, to some extent, in- 

 ferred from the circumstance of the Commissioners pointing 

 them out for special notice. " Although we are aware that 

 to point out the labours of individual members of the Com- 

 mission would be impossible, and that it may appear in- 

 vidious to single out one for praise, we cannot resist the 

 expression of our thanks to Mr. Hodgkinson for the zeal 

 and intelligence with which he has carried out the remark- 

 able series of experiments which are detailed in the Ap- 

 pendix A to this Report, and which constitute a large pro- 

 portion of those which have been already described ^' (see 

 the Commissioners' Report, page 15). Such, then, was 

 the estimate of the labours of Mr. Hodgkinson by Lord 

 Wrottesley, Prof. Willis, Col. James, Mr. Rennie, and 

 Mr. Cubitt ; and it has been amply confirmed by the en- 

 gineering experience of the last thirteen years. The ob- 

 jects for which Mr. Hodgkinson sought in this inquiry 

 were — 



1 . The determination of the longitudinal extensions and 

 compressions of long bars of cast and wrought iron by 

 weights varied by equal increments, up to that producing 

 fracture. 



2. The establishment of general formulse connecting the 

 longitudinal extensions j and compressions j and sets of cast 

 iron with the forces producing them. 



3. To determine the deflection of horizontal bars pro- 

 duced by various transverse pressures, and to compare the 

 effects with those produced by impacts. 



4. To determine general formulae connecting the trans- 

 verse pressure, the deflection, and set remaining after the 

 pressure was removed. 



