DIFFICULTY OF DISPROVING. 



all the heavenly bodies on all the human. He cites the case of a 

 child who always went into convulsions at the moment of full 

 moon. Pyson, another believer, cites another case of a paralytic 

 patient whose disease was brought on by the new moon. 

 Menuret records the case of an epileptic patient whose fits 

 returned with the full moon. The transactions of learned 

 societies abound with examples of giddiness, malignant fever, 

 somnambulism, &c., having in their paroxysms more or less 

 corresponded with the lunar phases. Gall states, as a matter 

 having fallen under his own observation, that patients suffering 

 under weakness of intellect, had two periods in the month of 

 peculiar excitement ; and in a work published in London so 

 recently as 1829, we are assured that these epochs are between 

 the new and full moon. 



13. Against all these instances of the supposed effect of lunar 

 influence, we have little direct proof to offer. To establish a 

 negative is not easy. Yet it were to be wished that in some of 

 our great asylums for insane patients, a register should be pre- 

 served of the exact times of the access of all the remarkable 

 paroxysms ; a subsequent comparison of this with the age of the 

 moon at the time of their occurrence would furnish the ground 

 for legitimate and safe conclusions. We are not aware of any 

 scientific physician who has expressly directed his attention to 

 this subject, except Dr. Olbers of Bremen, celebrated for his 

 discovery of the planets Pallas and Vesta. He states that in 

 the course of a long medical practice, he was never able to 

 discover the slightest trace of any connexion between the phe- 

 nomena of disease and the phases of the moon. In the spirit of 

 true philosophy, M. Arago, nevertheless, recommends caution in 

 deciding against this influence. The nervous system, says he, is 

 in many instances an instrument infinitely more delicate than 

 the most subtle apparatus of modern physics. Who does not 

 know that the olfactory nerves inform us of the presence ot 

 odoriferous matter in air, the traces of which the most refined 

 physical analysis would fail to detect ? The mechanism of the 

 eye is highly affected by that lunar light which, even condensed 

 with all the power of the largest burning lenses, fails to affect by 

 its heat the most susceptible thermometers, or, by its chemical 

 influence, the chloride of silver ; yet a small portion of this light 

 introduced through a pin-hole will be sufficient to produce an 

 instantaneous contraction of the pupil ; nevertheless the integu- 

 ments of this membrane, so sensible to light, appear to be com- 

 pletely inert when otherwise affected. The pupil remains 

 unmoved, whether we scrape it with the point of a needle, 

 moisten it with liquid acids, or impart to its Surface electric 



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