( 52 ) 



If a striated muscle is heated, it shortens: this is accompanied, as 

 appears from the experiments, by changes of hardness. In order to 

 trace this, the muscle in the sclerometer, instead of to a corkplate, 

 was fixed to the thin copper bottom of a temperator, now serving 

 as resting-surface. Through this temperator, as Thunberg pointed out 

 for the examination of the cold- and heat-points of the skin, alter- 

 nately cold and hot water could be made to circulate. The copper 

 bottom communicates the heat to the muscle; the temperature in the 

 temperator and that which the muscle gets, will not soon be the 

 same, but still is always in close connection with it. 



As a demonstration I give here a couple of photographic repro- 

 ductions of the oscillations of the beam of the sclerometer, as they 

 were made, and from which among others the above table was partly 

 derived. Fig. 3 gives the sclerometric reproduction of hardness of a 

 muscle at a temperature of 12.5° C. in the temperator, whilst fig. 4 

 shows the reproduction when the same muscle is heated to 56° C. 

 (See figs 3 and 4). 



If a muscle is heated to not too high a temperature, a decrease 

 of hardness manifests itself again after cooling, even though the 

 muscle does not quite reach its original degree of hardness. 



The subjoined table makes this clear. 



