The chemistry of plant and animal life . LABORATORY MANIPULATION 21 The student should take an inventory of his apparatusas soon as assigned a place in the laboratory. In caseany of the pieces are broken or missing, the attention ofthe instructor should be called to them. Always, at theclose of each days work, the apparatus should becleaned, placed in the desk, and the desk locked. Theapparatus and desk should always be kept in a neat andorderly condition. Untidiness is a frequent cause offailure in laboratory work ; neatness and careful atten-tion to details are necessary to success. 24. Cutt
The chemistry of plant and animal life . LABORATORY MANIPULATION 21 The student should take an inventory of his apparatusas soon as assigned a place in the laboratory. In caseany of the pieces are broken or missing, the attention ofthe instructor should be called to them. Always, at theclose of each days work, the apparatus should becleaned, placed in the desk, and the desk locked. Theapparatus and desk should always be kept in a neat andorderly condition. Untidiness is a frequent cause offailure in laboratory work ; neatness and careful atten-tion to details are necessary to success. 24. Cutting Glass Tubing.—Lay the glass tube on thetop of the desk or any flat surface. Draw a sharp three-cornered file across it two or three times, always on thesame place at which it is to be broken, until a scratch .smade through the annealed surface of the tubing. Take. Fig. I.—Breaking glass tubing. the tube in the hands with fingers and a thumb on eachside of the scratch (see Fig. i). The scratch should benearly between and on the side opposite the the hands tow^ard the body as if bending the tube, 22 AGRICULTURAL CHEMISTRY and at the same time press outward with the causes a square break of the tube. The cut ends ofthe tubing should then be held in the outer portion of theflame until the rough edges are annealed. 25. Bending Glass Tubing.—Place the wing-top at-tachment on the burner. Hold the tube in the upperpart of the flame as shown in the illustration (Fig. 2),
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