83 
This shortening amounts to about half the length of the muscle 
in rest, as found in the above preparation of the M. arrectores. 
It goes without saying that with this method, as well as by 
writing a contraction curve on a rotating drum, we obtain an 
imperfect image of what really takes place. The error made in this 
way is easily reduced to a minimal value, and is moreover easy 
of calculation, so that the true curves can be deduced from those 
obtained. 
Since, to my knowledge, Lrwanpowsky') is the only researcher 
who has written curves of a smooth muscle in warm-blooded ani- 
mals, contracting by indirect stimulation, it seems to me that valuable 
data may be obtained by using the method here described. 
1) Du Bois Reymonp’s Archiv. 1899. 
6* 
