History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c22: Chapter Viii. Chemistry In Rasendrachudamani Of Somadeva

History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c22

Language: English

Chapter Viii. Chemistry In Rasendrachudamani Of Somadeva

c22.1

Tests for *killed* iron (rouge):—*Killed* iron (or in general a *killed* metal), when heated with silver, does not mix or alloy with it.

*Antimony from Stibnite:*—*Nilanjana* (stibnite), mixed with *tikshnam* (cast iron) and strongly heated several times, yields a superior kind of lead, which is readily fusible and is of mild black colour.

c22.3

The resurrection of the dead metal (reduction of the *killed* or oxidized metal) is known as *utthapana* (lit. raising).

c22.4

Take lead of the weight of 30 palas and rub it with the milky juice of *Calotropis gigantea* and calcine it till its weight is reduced to a *karsha*: this residue, even if it be calcined a thousand times, will not undergo further decay (i e. diminution in weight). Metallurgists call this residue derived from lead *chapala*. (This possibly refers to the extraction of silver from argentiferous lead by a process similar to cupellation.)

c22.5

Tin also, similarly treated, will yield a *chapala*, which, on merely being touched with the hand, kills or fixes mercury. This mercury is recommended for metallurgical and not for chemical purposes.

c22.6

One pala of tin should be taken and rubbed with ten *nishkas* of mercury and made into a cake with the addition of zinc; it is then to be digested with the decoction of certain herbs and plants and warm vinegar, and afterwards once more rubbed with half a pala of blue vitriol and the juice of *Abrus precatorius*. The mass is then to be divided into small pills; these should then be put into a crucible with the lid on and the fire to be urged by means of bellows. The essence is then to be taken out of the crucible. This essence of the weight of ten *sanas* is then to be enclosed in a mixture of ashes and salts, and roasted. This essence of the weight of two *nishkas* is then to be fused with eighty times its weight of lead * * * *. This (essence) is also termed *chapala*. The process obviously gives rise to a brass-like alloy of copper, tin, zinc and lead. Mercury is volatilized during roasting and fusion.

c22.7

When quicksilver has been deprived of its physical properties (lustre, fluidity, etc.) it is known as *nashtapishta* or killed mercury (*cf.* Rasarnava, p. 139).

c22.8

Somadeva will now give a brief account of the apparatuses, after having consulted numerous chemical Tantras. (A description of a number of apparatuses is then given, which has been reproduced *verbatim* in Rasaratnasamuchchaya of the Iatrochemical Period; *vide infra.*)

Linked texts (2)

Rasaratnasamuccaya — Vāgbhaṭa (alchemist), Sanskrit
Rasārṇava — Sanskrit