Supplement to the Companion to the latest edition of the British Pharmacopoeia : including the additions, 1890 / by Peter Wyatt Squire and Alfred Herbert Squire.

Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: Supplement to the Companion to the latest edition of the British Pharmacopoeia : including the additions, 1890 / by Peter Wyatt Squire and Alfred Herbert Squire. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    -Saccharin is sufficiently pui'e as to aUow of its representation by this or any other characters and tests are practically aU contained in the current edition of the Couipanion, excepting the foHowing quaUtative reaction: On evaporating either Saccharin or 'Soluble Saccharin' with excess of strong Solution of boda, maintaining the residue in a state of semi-fusion for a few mmutes, cooling, dis- solving in Water, faintly acidulating with Hydi'ochloric Acid, and adding a few di-ops of Solution of Perchloride of Ii'on, a reddish-brown or pui-phsh colour is developed. Dm-ing the fusion an altaline Sulphite and Carbolate, as well as SaUeylate, appear to be foi-ined, as on acidulation the smeU of Carbohc and Hui- phui-ous Acids are both noticeable. SODA TARTARATA. ( Companion,''' page 378.) SeidHtz Powder is now made Official as— PULVIS SODiEl TARTARATA EFFERVESCENS. Tartarated Soda in dry powder, 120 grs. ; Bicarbonate of Sodium in dry powder, 40 grs. ; mix and wrap in blue paper. Tartaric Acid in dry powder, 38 grs. ; wrap in white paper. B.P. Dose.—The former powder dissolved in nearly half a pint of cold or warm Water, and the latter powder then added. SODII BENZOAS. ( Companion,' page 380.) This is now Official with the formula— NaCTHsOa, eq. 114. This salt may be obtained by neutralizing Benzoic Acid with solution of Car- bonate of Sodium and evaporating to di'yness. A white obscurely crystalline or amorphous powder, inodorous, or having a faint benzoic odoui-, of a sweetish alkaline taste, and a faiut aLkaUne reaction. Very soluble in water; soluble in 24 fluid parts of Rectified Spirit, and in 12 of boiling Rectified Spirit. When a quantity of the salt weighing 10 gi-s. is heated, it melts, emitting a benzoic odour, then chars, and finally leaves a residue weighing about 3-68 grains, which, when dissolved in water, requu-es for neutrahiiation from 69 to 70 grain-mea.sm-es of the volumetric solution of Oxalic Acid. An aqueous solution give a yellowish or flesh-coloui-ed preci]3itate when mixed with solution of Persul- phate of Iron. In former editions of the Companion the fonnula of this compound was given with an additional HoO, this being the composition of the crystallized salt. But as the ciystals are efflorescent, the formula now given approximates more closely (but yet_ not exactly) to the commercial salt made by the now Official method of evaporation to dryness. Three commercial samples lately examined contained an average of 4 p. c. of water, which has not been taken into account in the above quantitative tests, tlio figures which are given being apparently theoretical rather than experimental, and calculated upon an- anhydi-ous salt. The sample should, therefore, be preAdously dried at 212° F. (100° 0.) before weighing off' the quantity to be tested. Owing also to the practical impossibility of burning the residual charcoal from out of the semi-fused mass of Sodium Carbonate, we think the weight of the residue