Open AccessOn a static method of comparing the densities of gases
Publication year - 1906
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1906.0047
Subject(s) - pitot tube , pressure measurement , mercury (programming language) , mechanics , chemistry , analytical chemistry (journal) , materials science , physics , thermodynamics , chromatography , computer science , flow (mathematics) , programming language
The measurement of small differences of pressure to a fairly high degree of accuracy is not difficult. I have indicated a construction of a micromanometer which in its ordinary commercial form has a range of 3 or 4 cm. of height of a liquid column and reads to 0·005 mm. direct. Dr. Stanton describes a manometer constructed on Professor Chattock’s principle, having a reading sensitiveness of 0·0015 mm. of water, but the range is not stated. Lord Bayleigh, observing the contact between mercury surfaces and sharp points, obtained a sensitiveness of 0·0005 mm. of mercury with a range of about 1·5 mm. The idea of employing the micro-manometer for the determination of the relative densities of gases first occurred to me in 1901 in considering the corrections to a set of Pitot tube observations taken in a gas pipe situated some 20 feet above the manometer, and though a rough trial was carried out at the time it is only recently that I have had an opportunity of making an adequate test of the method.