together with rules deduced from numerous experiments for making an artificial water cement, equal in efficiency to the best natural cements of England, improperly termed Roman cements; and an abstract of the opinions of former authors on the same subjects

being an account, botanical and geographical, of the rhododendrons recently discovered in the mountains of eastern Himalaya, from drawings and descriptions made on the spot, during a government botanical mission to that country

embracing a consideration of all the photographic processes