Abstract: A flowmeter for fluids comprising a transparent vertical tube widening in upward direction, a ball freely disposed within said tube so as to be carried upward in dependence upon the flow, and a plurality of helical guide members on the inside of said tube, the guide members having inner edges which extend substantially vertically so that the free cross-sectional area for movement of the ball is substantially the same at all heights of the tube, the guide members minimizing pendulating of the ball and thereby increasing the accuracy of measurement.

Abstract: A device adapted to detecting leaks in an article having readily deformable walls has conventional arrangements for performing a leak detection by overpressure or by vacuum and has a deformable backup wall for engagement with the walls of the article. The backup wall is, on its face oriented towards the article, so configured that between the backup wall and the article there is obtained a coherent fluidtight space which may be evacuated.

Abstract: Lubricants for machining, deformation of machining and cold rolling of metals. The lubricant comprises an aqueous solution of at least one of the copolymers of ethylene oxide and higher alkylene oxides having 3 to 8 carbon atoms, of the copolymers of an acrylic acid or methacrylic acid and an acrylic ester, or a polymer of polyvinylpyrrolidone and/or of polyvinyl alcohol. The lubricants are useful in any operation involving the working of metals like steel, copper and the like. They have remarkable load-bearing capacity, and are biodegradable.