Year: 1889

page_text: I, CHARLES CARROLL GILMAN of Eldora, Iowa, in the United States of America,
Manufacturer of Porous Terra Cotta, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :-
The object of my invention is to provide a boiler-covering which is cheap, durable,
a good non-conductor of heat, and easily applied and removed; and to this end my
invention consists in the combination, with a boiler, of a sectional sheathing of terra
cotta lumber or porous burned brick material, applied in manner as hereinafter fully
described and claimed.
In the accompanying drawings which form a part of this specification, Fig. 1
represents a cross section of a boiler covered, with blocks of terra cotta lumber
according to my invention. Figure 2 represents the application to a boiler of tongued
and grooved sheathing blocks; Figure 3 illustrates the application of the terra-cotta
lumber blocks to that part of a boiler beyond the fire box, and Figures 4 and 5
represent another form of sheathing blocks with means for retaining the same in
place.
"
The material I employ as a boiler covering is known as the so called "terra-cotter
lumber." I do not, however, desire to limit myself solely to the use of said material,
as any porous burned brick material of substantially the same porosity as the terra
cotta lumber is within the scope of my invention. The cellular or sponge like
character of said material (due to the imprisoned sawdust being burned to ashes in
the kiln) makes the same an oxcellent non-conductor, for the numerous air cells in
the body of the material serve as so many dead air spaces to prevent the conduction
of heat. The said material may be moulded to the shape or forma desired, or it may
be sawed or cut with edged tools, and thus close-fitting joints secured.
In Figure 1 of the drawings, A represents the boiler, to which the blocks B,
solid or hollow, of terra-cotta lumber are directly applied, the same being laid up,
as shewn, in mortar of cement or of clay. In Figure 2 the blocks or slabs or
terra-cotta lumber are constructed so as to overlap by means of tongues 1 and
grooves 2, the said grooves being cut deeper than the length of the projecting
7

page_text: tongues, so as to leave a dead air space when two, blocks are joined between the
end of the tongue of one and the bottom of the groove of the other. In order that
the blocks of this form may be readily applied and as readily removed, I employ
the top or key block, C, which is provided with flanges or projections 3, to overlap
the tongues of the adjacent blocks and to preserve the continuity of the outer
surface. The said blocks may be cemented together, if desired.
In Figure 3 the blocks on the under side of the boiler are held in place by
a support or supports D, the upper blocks resting on the boiler and on the lower ones.
The block E, instead of being wedge shaped, as shewn, may be provided with
tongues for engagement with the adjacent blocks.
In Figures
and 5 the blocks are constructed so as to overlap by means of an
offset at each end on opposite sides, forming projections 6, by which construction all
of the blocks surrounding a boiler are permitted to be of the same form.
In Figure 5, the blocks 4 and 5 are half.blocks produced by cutting a whole block
into two parts. The half blocks may be moulded in the form shewn if desired.
These blocks are secured together by nails 7 applied at the places where they
overlap each other. In Figure 4 only the upper blocks need to be nailed together,
as the lower ones are held up by the support D.
The blocks shewn in the several figures may be shorter or longer than shewn
without involving a departure from my invention. All of the blocks illustrated are
laid lengthwise of the boiler shewn, so as to break joints with each other.
I am aware that plastic material composed of sawdust mixed with clay has been
applied to the surface of a steam pipe the said plastic material being covered by a
shell or pipe formed of baked porous clay made by mixing twenty five per cent. of
clay with seventy five per cent. of sawdust or coal dust and burned in a kiln, but this
differs materially from my invention and to it I lay no claim.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what
claim is :-
1. A boiler provided with a sectional covering of terra-cotta lumber the sections
of which are constructed and arranged to overlap for a distance sufficient to enable
nails driven through the overlapping portions to hold the sections together, substantially
as described.
2. A boiler provided with a sectional covering of terra-cotta lumber, the sections of
which are formed with an offset at each end on opposite sides, and are arranged to
overlap for a distance sufficient to enable nails driven through the overlapping portions
to bold the sections together, substantially as described.
3. A boiler provided with a sectional covering of terra-cotta lumber, the sections of
which are formed with tongues and with grooves of greater depth than the length of
the tongues so that when the sections are fitted together a dead air space is provided
substantially as described.
Dated this 19th day of February 1980