Improvements in Building or Paving Blocks.
Year: 1892

page_text: Date of Application, 8th Mar., 1892-Accepted, 9th Apr., 1892
COMPLETE STECIFICATION.
Improvements in Building or Paving Blocks.
1, GEORGE MAXWELL GRAHAM, of No. 169 Jackson Street, Chicago, in the
County of Cook and State of Illinois, United States of America, Civil Engineer,
do hereby declare the nature of this invention and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement:—
My present invention relates to that type of building or paving blocks, the
abutting sides or surfaces of which are provided with counterpart projections and
recesses so as to interlock together and be held in proper relative position or
alignment.
The object of the present improvement being to provide an improved construction
of such blocks, in which the surface formation is such as to afford a perfect inter-
locking of the one block with the other contiguous block or blocks, and which at
the same time avoids a sharp angular form in the cavities or recesses in said inter-
locking surfaces, that has heretofore been a serious element of weakness in former
constructions, owing to the fact that such sharp angularity of the recesses, serve as
a ready starting point for a fracture or crack in the main body of the block when
exposed to undue or unequal strain, sudden or excessive impact, etc.
I attain such object by the construction of parts illustrated in the accompanying
drawings, in which:
Figure 1, is a face view or elevation of the preferred form of my improved
building or paving block, as best adapted for general use in large constructions.
Figure 2, a section of the same at line -.c.
Figure 3, an elevation of a simpler form of the block.
Figure 4, a section of an elementary member of the present improved
construction.
Similar numerals of reference indicate like parts in the different views.
As represented in the drawings my improved building or paving block will have
a plane onter face 1, suitably divided or otherwise ornamented with depressions and
projections, and an inner face or back 2, either plane, ornamental, or formed with
interlocking ridges and depressions for interlocking with similarly formed blocks in
the construction of walls having a greater thickness than that of a single building
block of the present construction.
The four sides or surfaces 3, 4, 5, and 6, of the block are of an interlocking
formation which in the present invention consists of alternating ridges 7, and
depressions 8, curved on an equal radii which in my present construction divides the
sides or surfaces 3, 4, 5, and 6, of the block into a number of rows or series of
projections and recesses of a segmental spherical contour, the one row or series being
intermediately placed or "staggered" with relation to the next adjacent row or
rows, as clearly illustrated in Figures 1, and 2.
In its elementary form as shown in Figure 4, the block will be of an approxi-
mately spherical shape blending into that of an irregular hexagonal form, the top,
bottom and sides being formed on reversed curves of equal radii as heretofore
described, and the end or ends formed plane as shown to constitute an abutment for
a similarly formed elementary block. This elementary or individual form of the
block is not intended for practical use, as it does not afford the universal inter-
locking features that its integral combinations will afford, as illustrated in
Figures 1, 2, and 3..
In the formation of my improved building or paving block, any required number
of the elementary forms above described may be integrally united together to

page_text: constitute a block of the size and dimensions required, either small enough to be
readily placed by hand or large enough to require a derrick in handling.
In the manufacture of my improved building or paving block, any suitable
material may be employed, either artificial stone, terra cotta, clay, metal, or other
suitable compound or composition, in accordance with the special uses to which the
blocks may be applied.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. A building or paving block, having its sides 3, 4, 5, and 6, formed with inter-
locking projections 7, and recesses 8, of a segmental spherical forn, and equal radii,
substantially as set forth.
2. A building or paving block, having its sides 3, 4, 5, and 6, formed with rows
or series of interlocking projections 7, and recesses 8, intermediately arranged or
staggered and of a segmental spherical form, and equal radii, substantially as
set forth.
$
.
HERBERT & Co.,
18, Buckingham Street, Strand, London, W.C., Agents for the Applicant.