76 PHYSIOLOGY UF MUSCLES AND NKKYI-. 







In order In form some conception i>f tin- amount of 

 \vanntli thus generated, we will assume that the specific 

 warmth of muscle is the same as that of water. As the 

 greater part of muscle consists of water, 1 this assumption 

 cannot be far wrong. ]>v the specific warmth of a sub- 

 stance is meant that amount of warmth which is neces- 

 sary to warm one gramme of the substance exactly one 

 degree, the amount nece<-ary in the case of water being 

 regarded as the unit. Therefore about one unit of 

 warmth is requisite to warm one gramme of muscle 

 substance one decree. According to our assumption, in 

 each gramme of muscle substance at least '15 of a unit 

 of warmth is generated. Now it is known that each 

 unit of warmth is equivalent to 424 units of work, that 

 is to say, when warmth is transformed into mechanical 

 work, .JU4 grammes can be raised one metre by one 

 unit of warmth. If, therefore, no warmth were set free 

 from the muscle during tetanus, but if it were tran-- 

 formed into work, each gramme of muscle substance 

 would be able to raise 424-^-0-15 gramme to the height 

 of one metre. This amount, therefore, represents the 

 minimum of that which is accomplished as 'internal 

 work' in the muscle during tetanus. 



By soldering rods or strips of t wo metals alternately 

 on to each other so that all the points soldered an- 

 arranged in two planes, differences in temperature much 

 more minute than those which occur during tetanus 

 may be measured. Such an apparat u- is called a thermo- 

 pile. Heidenh: in had one of the.-e made of rods of 



1 ACCI rc'.'.ML' tn u ivo-nt M:itrinrnt nf Ir. Adamkiewicz, the spe- 

 cific \v:irintli I'!' musrV is even u-rratrr I li:ui I kit uf water, tliuu^li it 



bad previously been assumed that tin- sprriiic wurmtli >!' wain- is 

 greater tlian tlmi nf any otlii'r kimwn siili.st:nn-i', with tlio excep 

 nf liylr' 



