EXPERIMENTAL RESEARCHES IN CHEMISTRY AND PHYSICS. -----~---- Analysis of iVatit:e Caustic Lime*". OX THE NATIVE CAUSTIC LIME OF TUSCANY. By THE MARQUIS RIDOLFI. THE interesting communication of Dr. Giovacchino Taddei respecting his discovery of caustic lime in the water of the ancient bath of Santa Gonda, in August 1815, induced me to visit the spot. The following is the result of my researches :- The bath is situated in a laguna in the corner of a field near the high road to Pisa, whieh divides the plain called La Catena from the mountains of Cigoli and San. Miniato. The soil is a mixture of clay, calcareous earth, siliceous sand, and vegetable matter. There are two sources of water; one issues from the bottom of the laguna, and the other from the side. The first is hot, raising the thermometer of Reaumur to 35i-°. It is so saturated with lime, that upon cooling the water, it ? Quarterly Jonrnal of Sciencc, i. 2(iO. I reprint this paper at full lcngth. It was theTable of Contents