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earning properties. The blood is then brought into direct contact 

 with the small fibres, and the result is — pain. 



When the various electric cables, or nerves of the body, 

 reach the spinal cord, they divide into two parts. Those which 

 give the power of movement pass to the front of the cord, while 

 those which convey sensation enter the back part of the cord. 

 Sensory impulses, or "feelings," from the right side of the body 

 pass up the left side of the cord, and those from the left of the 

 body pass up the right. 



The rate at which "painful impressions" may travel from 

 the skin along the nerves of feeling to the brain is estimated to 

 be about the same as the rate at which the power of action passes 

 down the " motor " nerves when communicated from the brain 

 to the muscles. The actual speed at any given time is believed 

 to vary according to temperature, and other circumstances which 

 cannot be easily defined. It may sink as low as 30 miles per 

 second if the limb concerned is cold, or if the limb is heated it 

 may rise as high as 89 miles per second. 



Not a few have tried their hand at defining pain, and ex- 

 plaining the reason of its existence. Pathologists, theologians, 

 and philosophers have all spoken, and have found some kind of 

 an audience to listen to them. The pathologist says, " Pain is 

 the sign of diminished functional activity," — which is prosaic. 

 The theologian says, " Pain is the penalty of some broken law." 

 There is truth in the statement, but it is not the whole truth, 

 and nothing but the truth. The philosopher, " who has some 

 poetry in his make-up," says " Pain is the prayer of the nerves 

 for blood." Another definition, which Mr. Morgan thought 

 would recommend itself as "simple and suggestive," and as 

 emphasising the truth that pain is not an unmixed evil, is, 

 " Pain is the protector of the voiceless tissues." Pain is not in 

 many cases simply revenge for broken law, but its first object is 

 remedial. Of this the Lecturer gave a number of examples. 

 Among other things he said that chilliness, which is a species of 

 " painful impression," makes people walk faster, or draw near a 

 fire, and so ward oft' a cold or something worse ; or it may cause 

 a sneeze, which is Nature's attempt at arousing the nerve centres. 



But pain frequently passes beyond this beneficent stage as a 

 warning voice, and becomes a positive danger by its presence. If 

 it is really acute and continuous the general health sufters. In- 

 deed, it may be so acute as to cause fatal collapse, especially if 

 the heart is not sound. The organs of the body are capable of 

 becoming the seat of pain with dift'erent facility. No doubt 

 those nerves specially regarded as nerves of sensation are 

 generally those which conduct pain, but true sensations of 

 pain can be conducted through the nerves of special sense, 

 such as sight, hearing, &c., by increasing their specific energy. 



