The influence of barometric changes upon the body in health and disease / by Andrew H. Smith.

  • Smith, Andrew H. (Andrew Heermance), 1837-1910.
Date:
1881
Catalogue details

Licence: Public Domain Mark

Credit: The influence of barometric changes upon the body in health and disease / by Andrew H. Smith. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    11/16 (page 7)
    require a change of pressure so enormously disproportioned to any changes occurring from natural causes, that it would, be absurd to reason from one to the other. But the fact is, that observation of the effects of high pressure reveals a difTerence in the susceptibility of different persons to its influence which would not, a priori, have been expected, and which becomes a prime factor in calculating the effect of minor degrees of condensation of the atmosphere. Of the men employed under my observation in the cais- sons of the East River Bridge, a large proportion bore the excessive pressure (reaching at last to 36 lbs. additional to the square inch) without the slightest ill effect; while, on the other hand, some quite severe cases resulted from a very short exposure to the slight pressure employed in the early part of the work. For instance, a student of engi- neering visited the Brooklyn caisson, where the pressure did not exceed 15 lbs., and, after a very brief stay, was seized, on coming into the open air, with temporary paralysis. That a short exposure to a pressure of 15 lbs. should par- alyze one man, while another was able to bear, day after day, without inconvenience, a pressure of 36, or even, as at St. Louis, of 50 lbs., is to be accounted for only by assum- ing a vast difference in susceptibility, the limits of which difference in either direction can only be surmised. Back of this there is probably a difference in the efficiency of the vaso-motor system, or, perhaps, in the structure of the ves- sels themselves, so that, in one case, the vessels resume, at once, their normal condition, when the pressure is re- moved, while in the other, the abnormal distribution of the blood persists in certain localities. Whatever the predisposing condition may be in this lat- ter class of cases, we have only to assume its existence in an exaggerated degree, to bring the subject within the range of the influence of ordinary barometric changes. If