lar to that shown in the sketch below.

This consisted of a hollow wooden form of the dimensions indicated.
The mixture was to be poured into the hopper until the entire form was
filled, such mixture flowing down and along the horizontal legs and up
the vertical members. It was to be left until the mixture was hard, and
the requirement of the test was that there should be absolute uniformity
of mixture and mass throughout. This was finally accomplished, and
further invention then proceeded along engineering lines looking toward
the devising of a system of molds with which practicable dwellings might
be cast.

Edison's boldness and breadth of conception are well illustrated in his
idea of a poured house, in which he displays his accustomed tendency
to reverse accepted methods. In fact, it is this very reversal of usual
procedure that renders it difficult for the average mind to instantly
grasp the full significance of the principles involved and the results
attained.

Up to this time we have been accustomed to see the erection of a house
begun at the foundation and built up slowly, piece by piece, of solid
materials: first the outer frame, then the floors and inner walls,
followed by the stairways, and so on up to the putting on of the roof.
Hence, it requires a complete rearrangement of mental conceptions to
appreciate Edison's proposal to build a house FROM THE TOP DOWNWARD, in
a few hours, with a freely flowing material poured into molds, and in
a few days to take away the molds and find a complete indestructible
sanitary house, including foundation, frame, floors, walls, stairways,
chimneys, sanitary arrangements, and roof, with artistic ornamentation
inside and out, all in one solid piece, as if it were graven or bored
out of a rock.

To bring about the accomplishment of a project so extraordinarily broad
involves engineering and mechanical conceptions of a high order, and, as
we have seen, these have been brought to bear on the subject by Edison,
together with an intimate knowledge of compounded materials.

The main features of this invention are easily comprehensible with the
aid of the following diagrammatic sectional sketch:

It should be first understood that the above sketch is in broad outline,
without elaboration, merely to illustrate the working principle; and
while the upright structure on the right is intended to represent a
set of molds in position to form a three-story house, with cellar, no
regu