_The Value of Ramming._--"Beating, or compression, is used in many
different sorts of work; the ancients employed it in making their rough
walls; the Italians employ it for the terraces which adorn their houses;
the Moors for all their walls; the Spaniards, the French, and others for
some of the floors of their apartments. The intent of the ancient
architects, when they recommended the beating of cement and other
compositions used in building, was to prevent them from shrinking and
cracking; and it is employed for the same purpose in walls which are
made of earth. The beater, by repeated strokes, forces out from the
earth the superfluous water which is contained and closely unites all
the particles together, by which means the natural attraction of these
particles is made powerful to operate, as it is by other natural causes
in the formation of stones. Hence arises the increasing strength and
astonishing durability which houses of this kind are found to possess."
_An Experiment._--"Upon beating a small portion of earth, and weighing
it immediately afterwards, it was found to weigh 39-1/2 lb. Fifteen days
after, it had lost 4-1/4 lb. In the space of another fifteen days it
lost but 1 lb.; and in fifteen days after that its weight diminished
only 1/2 lb. In the space of about forty-five days the moisture was
completely evaporated, and its weight was diminished about one-eighth;
consequently only one-eighth of the whole mass was occupied by moisture,
and this small proportion cannot at all affect the solidity and
consistency of the earth so treated. This experiment is also sufficient
to show the difference between this kind of building and that vulgar
kind called in England 'mud-walling.'"
_Rate of Work._--"In one single day three courses of about 3 ft. each
may be laid one over the other; so that a wall of earth of about 8 or 9
ft., or one story high, may be safely raised in one day. Experience has
proved that as soon as the builders have raised their walls to a proper
height for flooring, the heaviest beams and rafters may without danger
be placed on the walls thus newly made; and that the thickest timber of
a roof may be laid on the gables of pise the very instant they are
completed."
[Headnote: Suitable Soils]