Charak Samhita
उष्णं तीक्ष्णं सरं स्निग्धं रूक्षं सूक्ष्मं द्रवं स्थिरम्। द्रव्यं गुरु च यत् प्रायस्तद्धि स्वेदनमुच्यते ॥१६॥
The drug or substance that is used for swedana (sudation) therapy possesses hot, acute, flowing (unstable), unctuous, dry, minute (subtle), liquid, stable and heavy qualities.
english translation
uSNaM tIkSNaM saraM snigdhaM rUkSaM sUkSmaM dravaM sthiram। dravyaM guru ca yat prAyastaddhi svedanamucyate ॥16॥
hk transliteration by Sanscript