The elements of pharmacy, and of the chemical history of the materia medica : containing an explanation of the chemical processes of the London pharmacopoeia on the different theories received at present : the chemical properties of various articles of the materia medica of the London College : and of other drugs that have been lately introduced into practice : a description of the most approved furnaces actually used in the practice of experimental and manufactring chemistry : illustrated by figures : the whole intended as a companion to the author's Treatise on pharmacology / by Samuel Frederick Gray.

  • Gray, Samuel Frederick, 1766-1828.
Date:
1823
Catalogue details

Licence: Public Domain Mark

Credit: The elements of pharmacy, and of the chemical history of the materia medica : containing an explanation of the chemical processes of the London pharmacopoeia on the different theories received at present : the chemical properties of various articles of the materia medica of the London College : and of other drugs that have been lately introduced into practice : a description of the most approved furnaces actually used in the practice of experimental and manufactring chemistry : illustrated by figures : the whole intended as a companion to the author's Treatise on pharmacology / by Samuel Frederick Gray. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    he made up by the depth of the air trunk below it. Some warehouses in the neighbourhood of Birmingham, are con- structed with descending flues to all the fire places, so that as good a fire may be made in the upper stories as in the lower, without smoking the rooms ; and on the cinders being pushed over the grate at the entrance of the descending flue, the ashes drop without any trouble into the cellar, where the descending flues terminate a little above the ground. This furnace is in more common use in the laboratories of drug- gists, than the preceding, for melting substances; and is generally the first close furnace that is thought of, after the stove holes ; indeed, these two, with a 12 in. sand pot, having a sand heat annexed, and a 30 gallon copper still and worm, usually compose the sett of furnaces that are used by a shop- keeping chemist and druggist in this country. Boerhaave's Reverheraiory.—If a furnace should be re- quired adapted to distillations by a naked fire, on a rather large scale, it can scarcely be made portable. The smallest construction is that of Boerhaave, which requires the use of long necks instead of retorts. It is to be built under a chim- ney, the internal cavity of the ash hole being a foot deep from front to back, and 22 in. long from side to side. This ash hole is built up 11 inches high, and has on one side an opening, which he orders to be the whole height of the ash hole, 4 inches wide, and to have a door that will fit close; but a hole 6 in. by 4, with bricks ground to fit it, and close it when necessary, seems sufficient. Three strong bars are then laid on the walls of the ash hole, from front to back, at equal distances, to support the long fire bars which reach from side to side, at about an inch apart, and the fire place built up in the form of an ellipsis cut off* at the foci, which are 20 inches asunder, the transverse diameter to be 15 inches, whence the latus rectum will be about 12 inches. Over the ash door, and 2 in. above the grate, a fire door is made 9 inches high and 7 wide, to be closed with a stopper. The walls are continued up to the height of 16 inches above the grate, but an opening is left in the front 10 in. above the grate, of a semi-elliptical form, 20 in. long and 12 in. high in the middle. On the back wall opposite to this opening, but an inch lower, a ledge of an inch and an half is left to support the long necks. A vent hole 3 in. wide and 2 high, is left in the upper part of the middle of the back wall. The furnace is then covered in bv an ellipti-