Page:Madras Journal of Literature and Science, series 1, volume 6 (1837).djvu/91

1837.] Remarks on the Figure.—The long limb A, is independent of the other, and the short tube B, with its cistern, stop cock, &c. screws on it at C. By this arrangement the long limb can be easily filled and the mercury boiled therein. When the short cistern limb is screwed on, while the other lays horizontally, mercury can be poured into the cistern to the level of the dotted line, and, from the peculiar shape thereof, the cistern will be as full as requisite, and very little air can remain in it on closing the stop cock. By inspection it will appear evident, that, turn the instrument as you will, the end of the long limb will be always immersed in mercury, and the contained air forced against the sides of the cistern. To keep the air in the cistern always in one part clear of the long or vacuum tube, if suspended in a box large enough to allow of its swinging freely on the hooks DD, no error will arise. The cistern end should always be carried uppermost in travelling or moving.
 * E. Iron bracket to support and steady the short limb.
 * F. A suspending iron and ring at the end of the long limb.

  Madras, 20th June, 1837.

,—At the close of my remarks on the cultivation of Senna, page 362 of your last Number, I mentioned an indigenous species possessing considerable medicinal properties, and added, that I should endeavour to procure specimens, from which to prepare a figure. I have now the pleasure to send you a drawing, rather too small to do justice to the subject, but so perfectly characteristic, so far as it goes, as to enable any one who may chance to meet with it to identify the plant—which is all that is wanted.

A recent notice in the public prints of a report by the 'Drug Committee' shows that it is the wish of government, to render this country as much as possible independent of foreign aid in the medical store department, by drawing on the resources of the country itself, for the supply of those medicinal agents required in the treatment of its more prevalent and dangerous forms of disease. As I have at different times paid a good deal of attention to medico-botanical subjects, you will, perhaps, under the protection of a medical plant, permit me to offer a few remarks applicable to the occasion of this paper, though less strictly 