In this article the author describes the geological characteristics of several monuments: the Jogeshwari caves in Bombay, the Ellora caves in the Trap Hills of the Deccan, Ajanta caves, Bagh caves, Konarak Temple and Kalsi. He also discusses the treatment used and the effect of the treatment. At the Jogeshwari caves the building material started crumbling because of volcanic eruptions. The caves must be isolated from the oozing mineral solution by digging a trench around them and paving the floors with cement concrete. Ellora caves suffer from water seepage. No solution has been found because if one crack is blocked, the water would force its way in some other direction. In Ajanta the problem is also the chemical action of water oozing through the cracks. The only remedy appears to be deforestation of the top of the hills, removal of the soil, and waterproofing the entire surface by coal-tar, up to the level of the base of the waves. The only way to preserve Bagh caves seems to be by the removal of the layers of limestone from the top, and isolating the caves completely. This will stop the water oozing through the joints of the sandstone and the junction of the sandstone and the limestone. The Konarak temple was made of <i>Khandolite; if the hydrolysis of clay can be stopped, further alteration can also be checked. The author sug-gests that after a coat of ochre a coat of gall-nut solution could be applied to make it waterproof. At Kalsi the growth of vegetation is a problem. An ammonia solution is used to remove the vegetation from the stone monuments. See also <i>AATA 12-48. -- AATA