NEW MEANS FOR PREVENTING EXPLOSIONS IN STEAM BOILERS MINES AND OTHER PLACES
Year: 1882

page_text: LETTERS PATENT to Thomas Sheehan of 49 Great Portland Street in the
County of Middlesex, for an invention of "NEW MEANS FOR PREVENTING
"
PROVISIONAL SPECIFICATION left by the said Thomas Sheehan at the
Office of the Commissioners of Patents on the 19th May 1882.
THOMAS SHEEHAN, of 49 Great Portland Street in the County of Middlesex
NEW MEANS FOR PREVENTING EXPLOSIONS IN STEAM BOILERS MINES AND OTHER
PLACES
"
This Invention has for its object improvements in preventing explosions in
steam boilers, mines and other places.
I insert into the upper part of the boiler a case containing a mixture of hydrate
of lime and black oxide of manganese.
Cases similarly charged serve as a protection against explosion in mines and
other places by absorbing or decomposing explosive matters which otherwise are
liable to accumulate.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Sheehan in the Great Seal Patent Office on the
16th November 1882.
THOMAS SHEEHAN of 49 Great Portland Street in the County of Middlesex
NEW MEANS FOR PREVENTING EXPLOSIONS IN STEAM BOILERS MINES AND OTHER
PLACES
This Invention has for its object the preventing explosions in steam boilers,

page_text: I insert into the upper part of the boiler a case containing a mixture of hydrate
of lime and finely powdered charcoal.
Cases similarly charged serve as a protection against explosion in mines and
other places by absorbing or decomposing explosive matters which otherwise are
liable to accumulate.
I make the mixture of hydrate of lime or slacked lime and powdered charcoal
These
in the proportion of 20 parts by weight of lime to 15 parts of charcoal.
substances should be finely powdered; they are to be intimately mixed in any
convenient manner.
The mixture should be kept until required for use, in air tight boxes. For use
in steam boilers I prepare cases of thin perforated sheet metal.
The size and dimensions of the case (or cases) must depend upon the form of the
boiler but the more extensive the surface exposed the better and the case should be
capable of containing a bed of the material several inches in thickness. The case
when charged is to be placed in the steam space of the boiler as far above the water
line as is convenient. It is sometimes convenient to provide guides within the
The cases
boiler on which the case or cases may be made to slide in and out.
should be occasionally examined to ascertain whether the material is still in active
and reliable condition. If it be found to effervesce when sulphuric acid is dropped
upon it, it is spent and should be replaced by a fresh charge.
I make similar arrangements to prevent explosions in mines, in this case I
provide a perforated sheet metal box or case upon wheels so that it may be drawn
along the rails in the mine as a trolley. The dimensions of the box or case may
conveniently be nine feet long by two feet wide and ten inches deep. The box or
case should be well perforated all over so that the mine gas may obtain ready
access to the charge of material which it contains. The box or case when in use is
to be drawn to any part of the mine in which it may be found that mine gas is
present.
As respects steam boilers it is my discovery that explosions are caused not by
the pressure of the steam but by the ignition and explosion of combustible gaseous
mixtures which tend to accumulate within steam boilers and the composition
herein specified effectually guards against all risk of explosion by absorbing and
oxidizing these gases as they are evolved from the water.
In a similar manner my means are efficaceous in preventing explosions in mines
and other places where explosive gases tend to accumulate.
Having thus described the nature of my said Invention and the manner of
performing the same I would have it understood that I claim my new means for
preventing explosions in steam boilers mines and other places consisting in the
combination of hydrate of lime or slacked lime and charcoal and the use of the
said combination substantially as described.
In witness whereof I the said Thomas Sheehan have hereunto set my hand
and seal this 18th day of October in the year of our Lord One thousand
eight hundred and eighty two.
THOMAS SHEEHAN (L.S.)