[Pramāṇa](https://indike.org/pramana/) › [Studies](https://indike.org/pramana/ins) › [Science, technology and education](https://indike.org/pramana/ins.science) › [History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray](https://indike.org/pramana/ins.science.ray-1956) › c23 # History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c23: Chapter Ix. Chemistry In Rasaprakasasudhakara Of Yasodhara History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c23 - **Language:** English ### Chapter Ix. Chemistry In Rasaprakasasudhakara Of Yasodhara ### [c23.1](https://indike.org/pramana/ins.science.ray-1956.c23.1) \*Preparation of Karpurarasa\* (calomel) :—Prepared from common salt, alum, borax and some vegetable drugs mixed with mercury. The mixture is heated in a closed pot. ### [c23.2](https://indike.org/pramana/ins.science.ray-1956.c23.2) Calomel is prescribed here only as an aphrodisiac and a specific for leprosy, but not as a remedy for syphilis. ### [c23.3](https://indike.org/pramana/ins.science.ray-1956.c23.3) \*Rasaka\* (calamine) :—Two varieties are known; \*karavellaka\* and \*dardura\*. ### [c23.4](https://indike.org/pramana/ins.science.ray-1956.c23.4) \*Extraction of Zinc from Calamine\* :—The process given is almost identical with that described in Rasaratnasamuchchaya of Iatrochemical Period (\*vide infra\*). The essence of \*rasaka\* possessing the lustre of lead runs out of the crucible. ### [c23.5](https://indike.org/pramana/ins.science.ray-1956.c23.5) \*Saurashtri\* or \*tuvari\* (alum-earth) :—Found in Surat; when applied to white clothes it serves as a mordant for dyes. A variety of it is slightly yellow and is called \*phullika\*. Another variety is white and acid in taste; this can kill iron. Alum is astringent, acid, beneficial to the eye; it can remove pimples and kill mercury \* \* \* The essence extracted from the alums (i.e. oil of vitriol) is to be used for operations with metals and not as medicine. ### [c23.6](https://indike.org/pramana/ins.science.ray-1956.c23.6) Descriptions of various kinds of pits for calcining and roasting purposes are given; as also their dimensions with the number of cow-dung cakes to be used as fuel, etc. ### [c23.7](https://indike.org/pramana/ins.science.ray-1956.c23.7) Here ends Chapter X of Rasaprakasasudhakara by Yasodhara, son of Padmanabha. ### [c23.8](https://indike.org/pramana/ins.science.ray-1956.c23.8) \*Hemakriya\* or process for the fabrication of gold :—"I shall now speak of some curiosities of metals, partly from my own experience and partly from the classics on the subject. Calamine, cinnabar, copper pyrites and realgar are to be rubbed with the milky juice of \*Euphorbia neriifolia\* for seven days together and then to be digested another three days. Melted copper or silver or lead, being alloyed with the aforesaid mixture, acquires the power of converting hundred times its weight of base metals into gold." ### [c23.9](https://indike.org/pramana/ins.science.ray-1956.c23.9) CHAPTER X ## Linked texts (2) - [Rasaratnasamuccaya](https://indike.org/pramana/in.med.rasa.rasaratnasamuccaya) — Vāgbhaṭa (alchemist), Sanskrit - [Rasaprakāśasudhākara](https://indike.org/pramana/in.med.rasa.rasaprakasasudhakara) — Yaśodhara (alchemist), Sanskrit --- Source: [https://indike.org/pramana/ins.science.ray-1956.c23](https://indike.org/pramana/ins.science.ray-1956.c23) · Pramāṇa