here great stiffness is required to support the floors. five hours, during which period the mixture is to be violent- sides, is provided with cylindrical walls, D, Fig. 2, which Fig. 6is a section of wall, showing how perfectly the plaster fit closely inside of box, A, and extend down below the… … this instrument is that plates may It is claimed that this device effectually prevents the es- rious forms by letters pa- be placed in the bath back up; float- cape of sewer gases from the pipe, B, as they cannot pass tent. It may be applied to ing particles of dirt are thus pre- down through the…
Internet Archive · Public domain (published before 1931). Free to use for anything.
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten20unit-939-421.webp)