they draw up: thus, in the circumstance already noticed as having occurred in the 14th regiment, we have every reason to rely upon its accuracy, which we could not have in a similar statement among the population of any country; and we have, I think, no reason to believe that in pronouncing the cholera of Ceylon not contagious, Dr. Davy, as well as two other gentlemen of high character and experience (Drs. Farrel and Marshall), have not gone upon such data as may bear scrutiny. LETTER III. Having given, in my last letter, Dr. Davy's views as to the cause of cholera, I may so far remark just now regarding them, that they are not new, or peculiar to him; and that it may be well, before Dr. Macmichael or others pronounce them vague, that they should inquire whether some of those causes have not been assigned for the production of certain epidemics, by one of the soundest heads of Dr. Macmichael's college--Dr. Prout, who seems, if we have not greatly mistaken him, to have been led to the opinion by some experiments of Herschell, detailed in the Philosophical Transactions of the year 1824. They should recollect that other competent persons devoted to researches on such subjects (Sir R. Phillips among the number) admit _specific local atmospheres_ (not at all _malaria_ in the usual sense of the term), produced by irregular streams of specific atoms from the interior of the earth, and "arising from the action and re-action of so heterogeneous a mass." For my part I feel no greater difficulty in understanding how our bodies, "fearfully and wonderfully made" as we are, should be influenced by those actions, re-actions, and combinations, to which Sir Richard refers, and of "whose origin and progress the life and observation of man can have no cognizance," than how they are influenced by other invisible agents, the existence of which I am compelled to admit.--If the writer of the article on cholera in the _Westminster Review_, for October, 1831, do not find all his objections met by these observations, I must only refer him to the _quid divinum_ of Hippocrates:--but I must protest against logic such has been employed by certain members of our Board of Health, who lately, on the examination of gentlemen of the profession who had served in India, and who had declared the disease not to be communicable, came to the conclusion that it must, nevertheless, be so, as those gentlemen could not show _what it was_ owing to.