14 T. L. Bolton and Donna L. IVithey 



fully introspect and observe the happenings in the palm during a 

 number of successive comparisons of the standard and the com- 

 pared pressures, he will find that the heavier — the case is the 

 same whether a heavier or a lighter pressure is used — pressure 

 may force the skin down deeper and so excite new points among 

 the internal tissues. Perhaps the skin is depressed against the 

 bone or against a tendon and so displaces it. Now, knowing that 

 this is a heavier pressure or that a heavier pressure is likely to be 

 given, this change in the location of the stimulation will be at- 

 tributed to the presence of the heavier pressure. Again, one ob- 

 serves that a greater recession of the hand has taken place be- 

 cause new local points on the hand's back are excited by its being 

 brought into closer contact with the support. The irradiations 

 of the tension in the skin from around the cork may extend to 

 points on the skin that are felt to have been unstimulated, while 

 the standard pressure was upon the palm. Other muscular con- 

 tractions than those before mentioned as being due to the pres- 

 ence of the standard may be discerned because of their differ- 

 ences in location ; the strains may reach farther out or spread in 

 other directions. If these observations be correct, and they are 

 easily verified, it will be seen that a heavier pressure is different 

 from the standard by the fact tTiat different local signs are ex- 

 cited by the heavier pressure. Let one, however, not be misled 

 by this shifting of the point of stimulation and these changes in 

 muscular tension and confine his attention as closely as possible 

 upon the cork and its point of contact with the skin, and try to 

 find out what are the differences in stimulations which two pres- 

 sures of greatly and easily discernibly different weights excite, is 

 there then anything of greater, that is, more intense, stimulation 

 by the one and less stimulation by the other? Does not one ar- 

 rive at the judgment of difference through the fact that one ex- 

 cites certain local signs that the other has left unexcited ? These 

 local signs may attach themselves first to the different points in 

 the skin's surface that -are depressed bv the cork ; the heavier 

 pressure depresses a greater area and this is determined by the 

 local signs of the parts so depressed. Or these local signs may 

 attach themselves to the different lavers of tissues between the 



1 88 



