78 Phenomena, 'fyc, of Heat-contraction of Skeletal Muscle. 



It is known from Diodorus that the great temple-building period 

 at Agrigentuin commenced after 480 B.C., and farther, the temple 

 the fourth on the list was incomplete as respects its roof in 406, and 

 was never finished afterwards. It was a huge temple, and the 

 orientation date for the foundation has great architectural prob- 

 ability. After a shock to its prosperity in 406, the city partially 

 recovered, and six years afterwards may have been able to found the 

 small temple with which I have closed the above list. Also the 

 orientation date of the temple at Paestum coincides exactly with a 

 passage in Herodotus in which, although he does not mention the 

 temple, he speaks of the celebrity of a Posidonian architect. 



"A Study of the Phenomena and Causation of Heat-contrac- 

 tion of Skeletal Muscle/' By T. G. Brodie, M.D., and 

 S. W. F. Richardson, M.B., B.S. Communicated by 

 W. D. Halliburton, F.R.S. Received March 2,— Read 

 March 11, 1897. 



(From the Physiological Laboratory of St. Thomas' Hospital.) 

 (Abstract.) 



In carrying out some experiments to determine the changes in 

 length of a muscle when subjected to varying loads and temperatures, 

 we have paid particular attention to those changes produced from 

 the onset of heat-contraction up to a higher temperature. We have, 

 for the particular study of these changes, always employed a sar- 

 torius preparation of a frog immersed in dilated defibrinated blood, 

 which was gradually heated in a water bath. The changes in length 

 were recorded photographically. The necessary tension was applied 

 by means of a very weak spiral spring. 



If the load be low — we have usually employed one below 1 gram — 

 the record shows four separate contractions. These are : — 



(1) A contraction commencing at about 32° C, and ceasing at 



about 40° C. 



(2) A s-econd commencing at about 46° C, and ceasing soon after 



50° C. 



(3) A third commencing at about 56° C, and ceasing soon after 



60° C. 



(4) A fourth commencing at about 63° C, and extending up to 



75° C. 



If we contrast the temperatures of these contractions with those 

 given as the points of coagulation of the proteids of frog's muscle 

 plasma by v. Fiirth, we find that the first three agree in all points 



