208 
ON LINIMENTUM SAPONIS. 
Formula. 
9? Castile Soap, 
Camphor, 
Oil of Rosemary, 
Rectified Spirits. 
Oij. 
v. 
Ed. 
J* Soap. 
Camphor, 
Spirit of Rosemary, 
Of the product afforded, according to the formula of the 
London Pharmacopoeia, Mr. Hallows says it is a " firm 
jelly, which cannot be poured out of a bottle without being 
melted by heat," and to obviate this and obtain a fluid con- 
sistence, after several experiments, he found the best means 
were to dilute the spirituous menstruum with a fourth part 
of distilled water, and to use the volatile oil of rosemary with 
rectified spirit, (see formula A. J. P. vol. i., pp. 180,) instead 
of spirits of rosemary. In the officinal formula above re- 
ferred to, it is obvious then, that the want of aqueous dilu- 
tion constitutes the defect. 
Let us now turn to the corresponding preparation in the 
U. S. Pharmacopoeia : The Tinctura Saponis Campho- 
rata. This article has given rise to several communications 
in our Journal, and it is admitted by practical pharmaceu- 
tists that the formula is defective, and that they are coerced 
to deviate from it. The principle difficulty consists in the 
want of permanent solubility of the soap in alcohol, as direct- 
ed of sp. gr. 0.835, and which does not contain a sufficiency 
Of water to retain it. Dr. Wood, in his comment upon this 
preparation, in the U. S. Dispensatory, (Ed. 1845,) remarks 
that "even this, the U. S. tincture, coagulates upon cooling, 
and requires the addition of a portion of water to enable it 
to retain the liquid form." The use of old hard castile soap 
is stated to create a greater difficulty, and the addition of 
three fluid ounces of water to the materials, is specified as 
being sufficient to prevent the coagulation at ordinary tern- 
