THE CHOLERA GAZETTE. VOL. I. _WEDNESDAY, AUGUST 8th, 1832._ No. 5. _M. Petit’s Treatment of Cholera._ The principal indication which M. Petit, one of the physicians of the Hôtel-Dieu de Paris, proposes to himself to fulfil, in the treatment of cholera, is to keep up a constant impression upon the spinal marrow, and to change the phenomena of innervation. To effect this he places over the whole length of the spine a strip of flannel, wet with a liniment composed of an ounce of the essence of turpentine and a drachm of aqua ammonia, and passes slowly over it a very hot flat-iron. An instantaneous evaporation of a great part of the liniment results, which acts powerfully on the skin over the spine, and induces very speedily vesication. The heat returns to the skin, the cramps and vomitings disappear, the circulation is reëstablished, and the patient feels much better. The effects of this remedy are assisted by hot bricks to the limbs; by frictions to the body with a decoction of mustard, to which some aq. ammonia is added, and the patient is also made to drink copiously of balm and mint tea. A table-spoonful of the following potion is likewise given every hour:--℞. Aq. distil. Tilleæ Europeæ; aq. distil. melissæ, āā. ℥ij.; tinct. opii, gtt. xx.; syrup. ether. ℥j. M. Finally, the patient is rubbed all over with a liniment composed of camphorated oil of chamomile, ℥ij.; laudanum, ℨij.; liquid ammonia, ℨj. M. Petit is said to have been more successful than most of his colleagues in the treatment of cholera. In a communication to the Academy of Medicine he states that under the above treatment two-thirds of his patients have recovered. _On Density of Population._ Density of population in cities becomes a matter of extreme importance connected with the visitations of pestilential diseases. A too crowded population may of itself engender a pestilence, and must inevitably aggravate one should it prevail from other causes. Hence the necessity which occasionally arises of thinning the inhabitants of certain districts--an exigency which, like that of war, often subverts civil authority, and demands the exercise of the most arbitrary power. We have recently seen our New York neighbours compelled to thin the population in some parts of their city, and we may yet be forced to have recourse to a similar measure. Upon this subject there are some interesting calculations furnished in Hazzard’s Register, (Vol. VIII. No. 5,) where may be found an interesting table, exhibiting the number of square feet in each ward of our city, together with the population at each census from 1790 to 1830, and the number of square feet to each inhabitant. From this table it appears that the increase in density of population throughout the city plot, has been in the following proportion during the forty years embraced in the estimate.