This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1838 edition. Excerpt: ... by mixing fat lime, in equal parts, with sand and natural or artificial puzzolana. By air slaking the result is the least good. This is understood as applying only to hydraulic lime stones which have been burned sufficiently to be employed as lime; as to those which hare been burned but very little, to be employed as cements, according to the process of Mr. Lacordaire, I have no experience that will enable ma to pronounce as to the tenacity of the mortars they afford. Au. It appears that by slaking in the air, the lime absorbs a considerable quantity of carbonic acid; and the mortar which results is filled with white points, which are particles of carbonate of lime, that cannot be made to disappear, whatever pains may be taken in the mixing process. The best mode of slaking hydraulic lime is to sprinkle it, as it comes from the kiln, with about one fourth of its bulk of water. A measure containing about one third of a cubic metre (a cube of about three feet three inches on each side) permits the mixture of the materials that are to compose the mortar, to be easily made. Before sprinkling the lime, it is to be surrounded with the mortars that are to be mixed with it, and when it is slaked and gives out no more vapours, it is to be covered with these mortars. The lime is left in this state for twelve hours at least, and for eight or ten days at most. The quantity of water necessary to bring the mortar to the ordinary consistence is afterward added. Care must be taken to make the mortar no faster than it is needed. The heap of lime surrounded by the sand and other materials should be covered from the rain. With common lime the process will be a little difficu