= Solution
\b[For the contemporary formulary, use boiling water for the <linseed>, <charcoal> and <mustard> <poultices>, and water at 100°F for the <yeast> <poultice>.] These are preparation temperatures, not temperatures at which boiling material is placed on <skin>.
For <Cataplasma Lini>, hot <water> hydrates the ground <linseed> into a cohesive moist mass; the contemporary account also notes the addition of <olive oil> when oil has been removed from the meal. For <Cataplasma Carbonis>, the hot bread-and-<linseed> basis is made with boiling <water>, then the <charcoal> is incorporated and part used at the surface. At ordinary atmospheric pressure the boiling-water preparation temperature is approximately $\boxed{212\,{}^\circ\mathrm{F}=100\,{}^\circ\mathrm{C}}$. <The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865)>[Relation of measures to weights of the British Pharmacopoeia, Cataplasmata; Carbo Ligni, charcoal cataplasm]{ref}
For <Cataplasma Fermenti>, the stated $\boxed{100\,{}^\circ\mathrm{F}\approx37.8\,{}^\circ\mathrm{C}}$ permits the <yeast> to ferment the flour mixture. Boiling would injure its fermenting activity. The flour, <yeast> and warm <water> are mixed and kept warm while the mass rises. This is a historical compounding process, not evidence that a fermented dressing treats every <wound>. <The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865)>[Cataplasmata, exception for Cataplasma Fermenti]{ref}
The <mustard> entry requires a historical qualification. The contemporary British recipe reproduced by the text directs powdered <mustard> and <linseed> to be mixed, then stirred into boiling <water>; the same text observes that excessive heat impairs development of the pungent <volatile oil>. Thus \b[“boiling” is the contemporary formula's instruction, while lukewarm preparation better preserves development of mustard's pungent <volatile oil>]. These are different claims. The later practical preference for lukewarm <water> should not silently replace the 1864 recipe, nor should that recipe be mistaken for optimal modern biochemical practice. <The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865)>[Cruciferae or Brassicaceae, Cataplasma Sinapis and effect of excessive heat]{ref}
Back to article page
