A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century A.D. v2.c34.336

v2.c34.336

Chemical action and Heat :—The operation of heat is of course universally implied in chemical combinations. Where the application of external heat is wanting, Vātsyāyana, the great Doctor of the Nyāya, points to the operation of internal heat. (e.g. पृथिवोधातुः अव्धातुना संसृहीतः आन्तरेण तेजसा पच्यमानः रसद्रवं निवर्त्तयति ।—Vātsyāyana-Bhāshya, Chap. IV, A'hnika 1, Sútra 47). In the case of combustion, we have seen Vijñāna-bhikshu explain the heat as latent in the Earth-substance, the fuel, from which it breaks forth. Udayana points out that the solar heat is the source of all the stores of heat required for chemical change in the world. The change of colours in grasses, for example, is due to Tejas, in the form of latent (invisible) heat, not in the form of Agni; and the cold in winter cannot take away this store derived from the Sun. (तृणादिविकारो हि यदि रूपादिपरा-वृत्तिमात्रहेतुः स नूनमौष्ण्यापेक्षेण तेजसा कर्त्तव्यः । तादृश च पाके अनिमित्तं हिममिति । न किञ्चिदनिष्टमापद्यते । न हि सौरस्य तेजसः त्रैलोक्यपाकहेतोर्हिमादपगमः क्षमते । अथ विकारो भस्मादिरूपो विवक्षितः सोऽसिद्ध एव हिमहतंषु तृणादिषु क विरोधो बाधो वा । अथ रूपादिपरा-वृत्तिमात्रेणैव अग्निः साध्यते तदशक्यम् । तस्य दर्शनस्पर्शनाग्राह्यस्य योग्रानुपलम्भाधितत्वात् अतादृशस्य तेजोमात्रस्य निवृत्तेरशक्यत्वात् अनिष्टत्वात् च । Udayana, Kiranávalí सृष्टिसंहारविधिनिरूपणम् ।) Similarly, it is under this solar heat that the unripe mango ripens, i.e. changes colour, taste, smell etc., showing that there is chemical transformation or subtile decomposition and recomposition going on; and this is also the case with the rusting of the metals, which is a combustion due to the solar heat (सूर्यपाक) even as the conversion of food into chyles and of chyle into blood are instances of chemical action due to the internal animal heat (जठरानल or औदर्य तेजः). But the kind of contact with heat-corpuscles, in other words, the kind of chemical action (पाक) which transforms colours is supposed to differ from that which transforms flavour etc. (विलक्षणतेजःसंयोग and पाक) and this last from that which produces a change of smell, or tactile quality. (पाको नाम विजातीयतेजःसंयोगः। स च नानाजातीयः। रूपजनको विजातीयतेजःसंयोगस्तदपेक्षया रसजनको विजातीयः। एवं स्पर्शादौ अपि तथा। एवं प्रकारेण भिन्नभिन्नजातीयाः पाकाः कार्यवलक्षणयेन कल्पनीयाः। तथाहि तृणपुञ्जनिष्प्राटमादौ उष्णलक्षणविजातीयतेजःसंयोगात् पूर्वहरितरूपनाशरूपान्तरस्य पीतादेरुत्पत्तिः पूर्वं रसस्य च्वन्नसैवानुभवात्। क्वचित् पूर्वं हरितरूपसत्त्वेऽपि रसपरावृत्तर्दृश्यते विजातीयतेजःसंयोगरूपपाकवशात् पूर्वं मनास्त्वरसनाशे मधुररसस्यानुभवात्। तस्माद्रूपजनकापेक्षया रसजनको विलक्षण एव गन्धजनको विलक्षण एवाङ्गीकार्य्यः। रूपरसयोर्परावृत्तौ अपि पूर्वं गन्धनाशे विजातीयपाकवशात् सुरभिगन्धोपलब्धेः। एवं