for example, from the bottoms of very large bottles. The extension tube b can be kept permanently in the bottle with a solid stopper in it. A pipet of any size with a rubber stopper on it is placed in the mouth of b, a U-shaped piece of glass tubing much constricted at both ends is pushed into a very flexible piece of rubber tubing a, and the latter attached to the end of the pipet. This glass tube prevents kinking, and in case the liquid accidentally spurts up the pipet i t slows its passage through the tube leading to the mouth. The mouthpiece of any shape goes in the other end of the flexible rubber tube. If it is constricted slightly it is the more easily inserted, and if it is curved like an S with its loops in planes a t right angles (Fig. 10e) it can be hung on the neck of tube b when not in use. The rubber tube can be left attached to it, and the other end of the rubber can he hung in the other loop of the S. Figure 106 shows a plug for the air inlet through stopper d. When solution is to be pipetted, the plug is removed, and if made in the shape of a shepherd's crook i t may be hung about the neck of tube b. When there is probability of the pipet being used again in a few days in the same bottle, the plug and pipet may be put in place and one end of the flexible tube a slipped on the pipet and the other on the end of the plug, making the bottle air-tight. A buret may be filled from the bottle in Figure 3 or Figure 10 by suction by passing the tip through a rubber stopper in the tube in the bottle and exhausting the air through a rubber stopper in the top of the buret. We have found apparatus shown in Figures 1, 3, 5a, and 9 most satisfactory in our class work. For making the apparatus shown in Figure 3, a nine-pound sulfuric acid bottle, a solid No. 5 rubber stopper, bored by ourselves, a No. 00 one-holed rubber stopper, and 14 mm. glass tubing of 12 mm. bore were used. The holes, c, were made with a paper punch. A nearly pure gum rubber tubing with a wall about 1 mm. thick was used for connecting pipets and mouthpieces. The troublesome coat of sulfur on rubber tubing and stoppers was removed by rubbing them with a wet file and rinsing with water.
Melon Ripening Hastened by Ethylene Gas Treatment. Casaba and honey-dew melons have been added to the list of fruits which can he given the color and texture of ripeness by treatment with ethylene gas, as a result of researches carried on by Dr. J. T. Rosa at the University Farmat Davis, Calif. Partly ripe melons, with rinds still green and flesh still hard, were subjected to the gas at a concentration of one part in 4000. They assumed the orthodox "ripe" mlar, and their flesh became soft. The sugar content, however, was not raised by the treatment. Far this reason the hastening gas treatment is not recommended for fruits picked before a fairly advanced stage of maturity.-Science Senrice
