AN IMPROVED PROCESS OF COLOURING AND STAINING MARBLE AND OTHER SUBSTANCES
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by John Zengeler. at the Office
of the Commissioners of Patents, with his Petition, on the 2nd
September 1871.
I, JOHN ZENGELER, of Chicago, Illinois, United States of America,
now of No. 8, Southampton Buildings, London, do hereby declare
the nature of the said Invention for "AN IMPROVED PROCESS OF COLOURING
AND STAINING MARBLE AND OTHER SUBSTANCES," to be as follows:-
-
My Invention relates to producing and fixing coloured designs upon
marble, ivory, and other similar substances. For this purpose I apply,
by means of a brush to dry marble or other similar substances an oily
liquid paste carefully freed from all moisture, and prepared by taking
any of the dried or anhydrous oily volatile solvents of the aniline
colours, such as naptha, bénzole, aniline oil, or such as are found
in the oily and volatile products of the distillation of coal tar, petroleum,

page_text: or equivalent substances, and combining any one or more of the same
with any one or more of the various colouring substances derived from
coal tar and similar substances.
The colours when applied become so permanently fixed by imbibition
as to be irremoveable by acids, alkaline, or any other solution, by wear,
or by the cleaning and polishing operations to which such substances are
commonly subjected.
The staining or colouration of the marble or other substance is remark-
able for variety and brilliancy of tint.
The application of the said colours in a liquid oily paste, from which 1
all moisture has been carefully excluded, prevents any blurring and
spreading, and gives to the lettering, flowers, or other designs a
definiteness, clearness, and delicacy of outline heretofore unattainable.
I take any one or any combination of the colouring materials and
dissolve the same in any one or more of the oily volatile liquids above 1
mentioned, always selecting by preference that one or that combination
of the same possessing the greatest power to dissolve or liquify the
particular colouring matter employed. The addition of the aniline
colouring matter is made in consecutive small portions, until it is
found by trial that the thick or pasty liquid obtained will make a 2
sharp and well defined line when applied to the marble or other
substance to be coloured without blurring or spreading at the edges.
When this condition is fulfilled the preparation will generally have
a syrupy or pasty consistency, and may be applied by means of a
brush to the marble or other substances upon the surface of which s
the letters, flowers, or other designs have been previously drawn with
a pencil or otherwise delineated.
If the marble or other substance has been previously freed from
superficial moisture the colouring matter may be applied without
using artificial heat because of the great penetrating power of the
anhydrous oily paste when applied to the dry stone, and my process
is therefore advantageous over all others with regard to economy of
manipulation.
When labour and expenso are not important and time of great value,

page_text: thereby opening the pores of the stone and hastening the process.
After the painting is finished it is best that the stone should in
all cases be heated to a temperature not exceeding 212° Fahrenheit,
whereby the volatile oil is expelled while the colouring matter is left
5 in the stone.