. Fresh-water biology. Freshwater biology. METHODS OF COLLECTING AND PHOTOGRAPHING 79 The end of the hose may also be lowered to near the bottom and may then, while pumping is in progress, be slowly drawn upward at a uniform rate. In this way is pumped a vertical column of water which extends from the bottom to the surface, and the volume of such a column may be calculated. The following forms of plankton pump may be referred to briefly. (a) Fordyce pump (Foidyce, i8g8). This invention of Professors Ward and Fordyce is shown in perspective (Fig. 21) and in sec- tion (Fig. 22). It "is prac
. Fresh-water biology. Freshwater biology. METHODS OF COLLECTING AND PHOTOGRAPHING 79 The end of the hose may also be lowered to near the bottom and may then, while pumping is in progress, be slowly drawn upward at a uniform rate. In this way is pumped a vertical column of water which extends from the bottom to the surface, and the volume of such a column may be calculated. The following forms of plankton pump may be referred to briefly. (a) Fordyce pump (Foidyce, i8g8). This invention of Professors Ward and Fordyce is shown in perspective (Fig. 21) and in sec- tion (Fig. 22). It "is practically a force pump. . The cylinder Lock liut. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ward, Henry Baldwin, 1865-1945; Whipple, George Chandler, 1866-1924. joint author. New York, John Wiley & sons, inc. ; [etc. ,etc. ]
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
