102 RESPO.VSE IN THE LIVING AND NON-LIVING 
allowed to cool down to its original temperature. The 
six following pairs of responses were then taken. 
That this beneficial effect of annealing was not due 
to any accidental circumstance will be seen from the 
fact that both wires have their sensitiveness equally 
enhanced. 
(4) In addition to this mode of annealing, both 
wires may be short-circuited and vibrated for a time. 
Lastly (5) shght stretching 7m sztw will also sometimes 
be found beneficial. For this purpose I have a screw 
arrangement. 
By one or all of these methods, with a little practice, 
it is always possible to bring the wires to a normal con- 
dition. The responses subsequently obtaimed become 
extraordinarily consistent. There is therefore no reason 
why perfect results should not be arrived at. 
Effect of single stimulus.—The accompanying figure 
(fig. 59) gives a series, each of which is the response- 
curve for a single stimulus of uni- 
form intensity, the amplitude of 
vibration being kept constant. The 
perfect regularity of responses will 
be noticed in this figure. The wire 

after a long period of rest may be in 
Fic. 59.—Usirorm Re- an abnormal condition, but after a 
SPONSES IN TIN : 
short period of stimulation the re- 
sponses become extremely regular, as may be noticed 
in this figure. Tin is, usually speaking, almost inde- 
fatigable, and I have often obtained several hundreds 
of successive responses showing practically no fatigue. 
In the figure it will be noticed that the rising portion 
