Improvements in or Connected with the Manufacture of Columns, Girders, and such like Articles for Building Purposes.
Year: 1889

page_text: Date of Application, 19th Feb., 1889
Specification Accepted, 30th Mar., 1889
Improvements in or Connected with the Manufacture of Columns,
Girders, and such like Articles for Building Purposes.
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 invention
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 this invention is to produce a new article of manufacture to be used
for building purposes.
It consists of the burned product of earthy and vegetable mixtures strengthened
by iron rods or cores closely united to the same substantially as hereinafter
described.
By the addition of fibrous vegetable matters to plastic clay mixtures a burned
product of considerable length, as for instance, ten or twelve feet has been obtained,
but the process of firing destroys the fibres and the burned product is not able to
withstand great transverse strains. This defect I remedy by strengthening the
product as follows: In moulding to form plastic mixtures of earthy and vegetable
matters with presses of expression I so arrange the die. in and through which they
pass that one or more longitudinal holes of given size are produced in or about the
centre of the column.
Subsequent to firing I fill the hole or holes with molten iron or steel. The earthen-
ware product by reason of its porosity, affords an anchorage for the molten material,
which when cooled forms an embedded rod or core closely united to the product, so
as to partake of its movement and not be independent of it when subjected to strain.
In this way the cores take up any strain, which they would not do if simply inserted
in boles in the material. Should the strength required of the product be so great
that the metal core from its size renders the splitting of the earthenware case likely
by reason of its weight or expansion when in a molten state, or if for purposes of
attachment protruding ends or other form of construction is desired, or wrought
metal be preferable to cast, a wrought metal rod of desirable form, solid or hollow,
and smaller than the longitudinal hole, may be inserted therein and securely fastened
to place by pouring into the hole around it molten metal of any sort, or even melted

page_text: brimstone asphaltum or other matter which becomes rigid when cool, the object sought
being to solidly embed the rod beyond the possibility of its moving independently
of its surroundings. Its inclination to bend under a weight is thus defeated,
whereas if an iron rod be ever so closely inserted in a material without this binding
it will bend and draw under strain and soon wear itself loose. The earthenware
product by reason of its porosity affords an anchorage for molten material. For some
uses to obtain the same result i.e. to overcome its disposition to twist loose in turning,
other forms than cylindrical should be used.
In the accompanying drawings Figure 1-is a view of a column with parts broken
away, Figure 2 is a cross section thereof.
A represents a block of terra-cotta lumber strengthened by means of iron rods or
cores a embedded therein. In this instance the material is shewn in the form of a
column in one piece with two cores, but a single core may be used, or any number.
The column or other similar structure may, however, be formed of a number of
pieces united in any suitable manner. The material in which the rods are embedded
is an excellent non-conductor of heat and cold, and will not crack like ordinary
terra-cotta when. subjected to the action of heat and water. With the strengthening
cores it forms an excellent material for building purposes to form girders, arches,
floors, walls, and in all locations where a strong and light building material
is required. It may be prepared for the market and for transportation in different
shapes and sizes.
I am aware that it is not new to insert rods of wire in fire-brick, and stove-linings,
and such I do not 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 1
claim is
1. As an article of manufacture, a burned earthenware product obtained from a
mixture of earthy and vegetable matters, and having an iron core or cores held therein
and engaging the pores of the material substantially as described.
2. As an article of manufacture, a burned earthenware product obtained from a
mixture of earthy and vegetable matters and strengthened by an iron rod or rods closely
united thereto, in a manner substantially as described.
3. A column or girder consisting of a burned earthenware product obtained from a
mixture of earthen and vegetable matters, having one or more strengthening cores
united to the material by casting, substantially as described.
Dated this 19th day of February 1889.
.