Measures to secure a patent for improvements in the above have been taken by Stephen Waterman, of Williamsburgh, N. Y., the original invention having been patented on the 28th of Dec, 1852. It is an improvement on the plan for preventing the serious casualties consequent to boiler explosions, which was noticed on page 108 of the present volume. It will be recollected that a u safety chamber was placed upon the boiler,and that when the steam attained an undue pressure it tore a plate which separated the chamber from the boiler, and as the steam gained additional space, its pressure on the square inch was reduced. This plan, although completely effective, involved the necessity of a large safety chamber, it is to reduce the dimensions of this appliance, that the present patent is chiefly designed. A reservoir ot cold water is pi aced in juxtaposition to the boiler and its appurtenances, so that the top communicates with the boiler and the bottom with the safety chamber, both communications being opened and closed by cocks. By this contrivance, when the plate bursts, its disruption acts upon an arrangement which opens both communications, and the steam pressure on both sides of the water being equalized, this latter fluid, by its gravity, will descend into the chamber and condense the steam, or if considered preterable, it might pass directly into the boiler.