Apr., 1918
T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY
t h a t Sample I11 was not genuine desiccated skimmed milk powder. CHEMICAL LABORATORY UNIVERSITY OF MINNESOTA MINNEAPOWS, MINNESOTA
AN IMPROVED AUTOMATIC PIPETTE-WASHING DEVICE By AUBREYVAIL FULLER Received November 17, 1917
Since his publication of a n article in THIS J O U R K A L , Vol. 9 , p. 1046, entitled “A Convenient Automatic Device for Rapidly Washing Pipettes,” the author has designed a modified form of the apparatus referred to, which embodies several improvements. I n the accompanying illustration A is a cylindrical metal t a n k , provided with a siphon, B , and a n inlet pipe, C. D is a brass rod which carries a t its lower extremity a disk of rather heavy brass gauze, t o which is fastened three legs of such length t h a t when placed in the cylinder the gauze is supported a t a level slightly above the tops of the two lower orifices. There should be about in. clearance all around between disk and tank. The operation of t h e device is as follows: Water is admitted through the inlet C which is connected t o the supply t a p , a t such a rate t h a t the speed a t which t h e siphon empties the tank is somewhat greater t h a n the speed a t which the tank is filled. The pipettes t o be washed are then placed, tip up, in the tank, the lower ends resting on the gauze. As the tank is alternately filled and emptied the pipettes are rinsed. T o remove the pipettes they are raised t o within easy reach by means of the “lifter” D . With a n apparatus of the dimensions of t h a t pictured, the period of a complete cycle is approximately
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45 sec. Inasmuch as two cycles are required for the average pipette, only about one and one-half minutes are necessary for thorough rinsing. Its capacity in terms of 2 5 cc. transfer pipettes is 13, and in terms of I cc. measuring pipettes about 100, when loosely packed. The time economy 0 ‘ of such a device over hand washing is thus apparent. The points in superiority of this device over the one previously described are : (I) greater capacity, (2) smaller table space occu, pied, (3) lower first cost, I (4) cleansing of both outside and inside of pipette. I It might be mentioned t h a t an apparatus of this I type would find particular 9 I; A application in laboratories conducting serological work, I where large numbers of pipettes must be rinsed , before sterilization. Its ,I field of usefulness is, how1 ever, entirely general and I I, the details of its construcI tion admit of wide variaI I tions t o suit peculiar conI ditions.
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BIOCHEM. DIVISION BUREAU O F ANIMAL INDUSTRY u. s. DEPARTMENT O F AGRICULTURE WASHINGTON, D. c.
ADDRESSES METHODS OF GAS WARFARE’ By S. J. M . AULD, British Military Mission
All I can do in the short time available is to give you, if I can, a general idea of what gas warfare really means on the Western Front at the present time. Some of you may have gotten the idea that gas is just an incident, and that there is not as much attention being paid to it as there was two years ago. That idea is entirely wrong. Gas is used to a tremendous extent, and the amount that has been and is being hurled back and forth in shells and clouds is almost unbelievable. I will try to give you a general idea of what is occurring and make the lecture rather a popular than a technical description. I shall also, for obvious reasons, have to confine myself to describing what the Germans have been doing, and will say nothing about what we are doing. Possibly the best plan would be to state more or less chronologically what occurred. I happened to be present a t the first gas attack and saw the whole gas business from the beginning. The first attack was made in April 1915. A deserter had come into the Ypres salient a week before the attack was made, and had told us the whole story. They were preparing to poison us with gas, and had cylinders installed in their trenches. N o one believed him a t all, and no notice was taken of it,-
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Report of a lecture delivered before the Washington Academy of Sciences on January 17, 1918. Reprinted from the Journal of the Washinelon Academy of Sciences, 8 , No. 3 , February 4, 1918.
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Then came the first gas attack, and the whole course of the war changed. That first attack, of course, was made against men who were entirely unprepared-absolutely unprotected. You have read quite as much about the actual attack and the battle as I could tell you, but the accounts are still remarkably meager. The fellows who could have told most about it didn’t come back. The Germans have claimed that we had 6000 killed and as many taken prisoners. They left a battlefield such as had never been seen before in warfare, ancient or modern, and \ one that has no compeer in the whole war except on the Russian front. What the Germans expected to accomplish by it I am not sure. Presumably they intended to win the war, and they might conceivably have won it then and there if they had foreseen the tremendous effect of the attack. It is certain that they expected no immediate retaliation, as they had provided no protection for their own men. They made a clear and unobstructed gap in the lines, which was only closed by the Canadians, who rallied on the left and advanced, in part through the gas cloud itself. The method first used by the Germans, and retained ever since, is fairly simple, but requires great preparation beforehand. A hole is dug in the bottom of the trench close underneath the parapet, and a gas cylinder is buried in the hole. It is an ordinary cylinder, like that used for oxygen or hydrogen. I t is then covered first with a quilt of moss, containing potassium car-
