Melville Fuller

“ We have already seen that Kearney and Tronson, who were experienced and practical railroad men, declared in their original applications for the patent, and for the reissue, that the shape of their grating was not material, and that it might be made either from bars or netting or perforated plates; and if their particular construction of grate with the ln g, vertical bars was a mere equivalent for the grates shown in the prior patents, then it would not be a patentable invention, but a mere change of form. ”

“ The strong draft created by the exhausting steam up the pipe into the chimney brings the coals and sparks to the grating, against which they strike, and fall harmless into the space in the smokehead. [The force of coals drawn from the fire, when impelled by the exhaust steam up the chimney, is such as to cut through netting, and even cast iron over a quarter of an inch thick, in two or three months, in any description of spark arresters located in the smokestack.] ”

“ B is a space commonly called the 'smokebox.' C, C, are the flues at the point where they enter the smokebox; E is a pipe extending from within the base of the smokestack down into the smokebox, and commonly termed a 'petticoat pipe.' D is a grating placed at the lower part of the petticoat pipe to prevent any cinders or sparks passing into the same. ”