Show WHAT IS A INCH A recent article entitled where water comes high discussing the quantity of water commonly called a miners mine rs inch states that the general government fixes the quantity as one cubic foot in 50 seconds I 1 have consulted all available authorities on she he subject and can find no men mention t ion of the volume of a miners inch being fixed by the general government in california where the term originated it is a well known fact that the miners inch is about as definite a quantity as a pall pail of water and hydraulic engineers have been trying for years to have the arbitrary term discarded for the cubic foot per second and acre foot in california custom seems to have made the miners inch as equal to one cubic foot in 50 seconds but this depends much on geographical location in colorado the statutes fixed the miners inch as equal to a quantity of water flowing from an inch square orifice under a pressure of five inches above the top of the orifice and assumes that the quantity of water delivered I 1 is proportional to the area of the orifice but this is far from being true for instance it if a flow of miners inches be required the volume obtained would be 33 42 47 cubic feet per second according as there were holes one inch square one opening one inch deep and inches long or one opening 12 inches square the tops of all opening being five inches below the surface of the water weir measurements are much more acu acierate erate and could almost almont always be substituted for the method by orifices the science of hydraulics has made considerable sid erable progress within the last decade but the multiplicity of detail necessary to consider in the accurate measurements of water renders many of the approximate rules valueless and the best methods are none too rood good it is to be hoped that in view of the increasing use and value of water for power irrigation and domestic purposes the miners inch as a standard will be relegated to innocuous desuetude and the more definite measurement of second foot used in preference for irrigation purposes the acre foot is generally coming into use on account of the convenience veni ence in in making calculations the acre foot is one acre covered one foot deep with water or cubic feet the article also referred to makes the statement that a miners inch presumably under a six inch pressure serves to irrigate acres of land the writer was for some years connected with the bear valley irrigation 11 company of redlands cal and under this system the is one miners inch to ten acres the average 4 beino being 6 one inch to four acres the juraga land water company near san bernardino use one inch to irrigate nine acres other parts of california f ornia use 0 one ne miners six inch pressure for from four to ten acres J H cunninham cunningham 0 in portland mining review |