380 ANNUAL OF SCIENTIFIC DISCOVERY. 







as to the singular and suggestive nature of the phenomenon. It appear?, 

 moreover, that if the sensibility of the sensitive spot be destroyed, then the 

 Guinea-pig eea.ses to be liable to epilepsy. Applying this fact to human 

 physiology, Dr. Brown-Sequard says that there is in the human body a 

 spot, discoverable, as he believes, by galvanism, which, if deprived of its 

 sensibility, would, in like manner, completely prevent attacks of epilepsy. 



PHYSIOLOGICAL KNOWLEDGE GAINED THROUGH CHLOROFORM. 



The following is an extract of a letter addressed to the Medical and Surgical 

 Reporter, London, by Dr. Charles Kidd, July 18-39 : 



" It is only within a few weeks that it has been clearly proved that the 

 endowment called common sensation, the great root of consciousness, as 

 shown by Locke, Leibnitz, and Schlegel, is not psychologically the same 

 a< the sense of touch, with which Dr. Snow and others have confounded it. 

 Thus a man may have a red-hot iron applied to his arm or leg under the 

 influence of chloroform; he feels no pain, but he feels the iron as an affair 

 of touch streaking out lines on his skin. The bearing of this fact on the 

 phenomena of insanity, sleep and dreams, is most extensive. In the same 

 manner, a woman in labor, with proper doses of chloroform, feels no pain, 

 but is quite conscious of the process of parturition quoad, the muscular 

 sense (that would be agonizing cramps otherwise) going on as usual. This 

 has only recently been shown, by M. Brown-Se'quard, to depend on the fact 

 already stated, but not suspected by Dr. Snow, who chiefly experimented 

 on rabbits and dogs. Indeed, a new world has, since his death, been opened 

 up as regards the psychology of chloroform in relation to ordinary sleep, 

 common sensation, touch, dreams, sympathetic action, emotion, reflex action 

 of the sensorium or soul itself, on the body, etc., so that the subject is only 

 iu its infancy." 



CELL DEVELOPMENT. 



Yirchow, the eminent German physiologist, in a recently published scries 

 of lectures, on what may be called " Cellular Physiology," defines the cell 

 to be an exceedingly minute microscopic object, consisting of a membrane 

 containing a substance in which is a nucleus upon which the action of the 

 cell depends. All pathological processes proceed from changes in and mul- 

 tiplications of previously existing cells. A cell can only arise from a pre- 

 existing cell, and never de novo. The germ of life is a cell transmitted and 

 impregnating an ovum. The whole scheme of animal development, both 

 physiological and pathological, is but a continuation of the process begun 

 in the ovum upon the cell the first step in gestation. He denies the 

 formation denovo of " granules/' or any other tissue form of the old pathol- 

 oii'ists, from a so-called Blastema or of homogeneous exudation. That is, 

 since the creation of the first man and woman, the race has been kept up 

 by, and every physiological and pathological phenomena has had its origin 

 in, the division and multiplication of cells the difference between the phe- 

 nomena of physiology and pathology being only that of normal or morbid 

 action iu similar forms. 



CHANGES OF THE BLOOD-CELLS OF THE SPLEEN. 



The opinions of physiologists as to the functions of the spleen, have been 

 various. Some, as Funke, Hewson, Bennet, etc., believe it to be a generator 



