A Note on an Apparatus Designed to Take Samples of Waters from Wells, Tanks, Etc., at Stated Depths

It is generally recognized that the surface water from a well or tank is not a fair sample of the average quality of its water. It is, therefore, of considerable importance, especially when taking samples for bacteriological examination to obtain water from a depth of about 3 feet from the surface and to avoid contamination from the upper layers. Various apparatuses have been designed for this purpose, some of which require evacuated sealed flasks, while others involve complicated rubber connections and are, therefore, not suited for general use in this country. Moreover, in almost all the apparatuses described in the textbooks, there is no arrangement to close the opening through which the water enters the bottle or the flask when it is withdrawn, and there is no absolute surety of the container getting completely filled at the required depth. There is, therefore, a certain amount of risk of contamination from the surface water when the apparatus is withdrawn. A simple apparatus has been designed for this purpose and is described below.