Specification of Thomas Stephens and Moses Hadley : double concave steam boiler.

  • Stephens, Thomas
Date:
1857
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Thomas Stephens and Moses Hadley : double concave steam boiler. Source: Wellcome Collection.

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    Stephens <$• Hadley s Double Concave Boiler, $■<?. Invention, and in what manner the same is to be performed, by an instru¬ ment in writing under their hands and seals, or the hand and seal of one of > them, and cause the same to be inrolled in the High Court of Chancery within four kalendar months next after the date of the said Letters Patent, that then the said Letters Patent, and all advantages thereby granted, should 5 cease and become void. NOW KNOW YE, that the said Thomas Stephens, in pursuance and per¬ formance of the said proviso, doth hereby describe and ascertain the nature of the said Invention, & in what manner the same is to be performed, as follows, that is to say:— -•••••** * 10 The said boiler is made of copper or iron plates, hammered and riveted together in the ordinary way, and of the ordinary form and make of the boilers now in comon use in atmosphere engines, and for the like purpose of boiling water for raising steam by which those engines are worked, with the following differences, that is to say: the bottom of the said new invented boiler is of 15 an uneven form or make, some parts thereof descending or projecting below the other parts thereof in two troughs or hollows, the inward trough or hollow forming a circle round the middle concave or open space, which concave or open space is about three feet six inches diameter and three feet six inches in depth, and which inward trough or hollow is about three feet six inches in 20 depth and one foot in breadth; and at about one foot distance from the said inward trough or hollow there is another trough or hollow of about two feet in depth and one foot in breadth, forming also a circle round the said inward trough or hollow, the space or distance between the said inward and outward troughs or hollows forming a second concave or open space of about one foot 25 in breadth for the fire to pass through from the middle concave or open place, under which middle concave or open place the fire is placed ; which said new invented boiler, being set in a spiral form, admitts the fire (which passes through each concave or hollow place) to play round and between the said troughs or hollows, and also by the help of a flanch or elbow of about one foot in breadth, 30 that projects from the top of the said outward trough or hollow, there is an open space between the said boiler and the brickwork for the fire to pass and coinunicate with the outside of the lower part of the said boiler and flanch, by which means the water contained in the said troughs or hollows and other parts of the said new invented boiler, is heated by a considerable less quantity 35 of fire, and also produces a greater quantity of steam than is produced by the coinon boilers now in ordinary use; and such trough or hollows and concaves, or open spaces in the bottom of the said new invented boiler, may be made of greater or less width or depth, or more or fewer in number, according to the
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