88 PHILOSOPHICAL TRANSACTIONS. [aNNO ITQl. 



These attempts towards an analysis of James's Powder, are followed by expe- 

 riments relative to its synthesis, which constitute the 2d part of Dr. P.'s inqui- 

 ries. Though the inability to prepare James's Powder would not prove the pre- 

 ceding conclusions, with respect to its composition, to be erroneous ; the being 

 able to compose a substance possessing all the same properties as James's Powder, 

 by uniting or mixing together the substances shown by the above analysis to enter 

 into its composition, would afford (he remarks) all the proof and demonstration 

 which can be had in the science of chemistry. 



The above analysis showed no essential ingredients of James's Powder but 

 antimonial calces, phosphoric acid, and calcareous earth, which 2 last sub- 

 stances appeared to be united together ; but it would have been vain and unne- 

 cessary labour to have attempted to make this powder by mixtures of any of the 

 commonly known calces of antimony and phosphorated lime ; because none of 

 them, from their well-known qualities, could form a powder of the same colour 

 and specific gravity as James's Powder, and like it partially soluble in acids. 

 From the above experiments however, ihe probability was evident, that this 

 substance might be made by calcining together antimony and bone-ashes ; which 

 operation produces a powder called Lile's and Schawanberg's fever powder ; a. 

 preparation described by Schroeder and other chemists 150 years ago. The re- 

 ceipts for this preparation ditt'ered in the proportion of the antimony to the bone- 

 ashes, and in the state of the bone ; some directing bone shavings to be pre- 

 viously boiled in water ; others ordered them to be burnt to ashes before cal- 

 cining them with antimony ; and in other prescriptions the bone shavings were 

 directed to be burnt with the antimony. According to the receipt in the posses- 

 sion of Mr. Bromfield, by which this powder was prepared 43 years ago, and 

 before any medicine was known by the name of James's Powder, 2 pounds of 

 hartshorn shavings must be boiled to dissolve all the mucilage, and then, being 

 dried, be calcined with 1 lb. of crude antimony, till the smell of sulphur ceases, 

 and a light grey powder is produced. The same prescription was given to Mr. 

 Willis, above 40 years ago, by Dr. John Eaton, of the College of Physicians, 

 with the material addition however, of ordering the calcined mixture to be ex- 

 posed to a great heat in a close vessel to render it white. Mr. Turner made this 

 powder above 30 years ago, by calcining together equal weights of burnt harts- 

 horn and antimony in an open vessel, till all the sulphur was driven off, and the 

 mixture was of a light grey colour. He was also acquainted with the fact, that 

 by a sufficient degree of fire in a close vessel this cineritious ])owder turned white.* 



* It is probable, that this powiler was matle for several years with merely the heat necessary to 

 cany off the sulphur and calcine tlie bone, in an open vessel over a charco;il tire in a common grate, 

 and consequently it was of a light clay or ash-colour. In this manner, Mr. Bromfield told me, he 

 prepared Scha\» anberg's powder 46 or 47 years ago. Its property of turning white in a greater de- 

 gree of fire appears to liave been a subsequent discovery. — Orig. 



