SIMPLE DEVICE FOR PI- PETTING OBNOXIOUS LIQUIDS

above the graduation mark. Now close the screw clamp. Loosen the stopper from the flask to release the pressure and gradually drop the surface of the ...
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JOURNAL OB CHEMICAL EDUCATION

JANUARY,

1929

SIMPLE DEVICE FOR PIPETTING OBNOXIOUS LIQUIDS LEOP~LD SCHEELAN, SYRACUSE UNIVERSITY, SYRACUSE. NEW YORK The apparatus consists of a Florence flask A, a two-hole rubber stopper carrying a piece of glass tubing bent a t an angle of about 45' to which an atomizer bulb B is attached, and the pipet P, which is fitted with a short piece of gum rubber tubing, and a screw clamp C. Tooperate the device, slightly open the screw clamp and by lightly squeezing the bulb force the liquid into the pipet well above the graduation mark. Now close the screw clamp. Loosen the stopper from the flask t o release the pressure and gradually drop the surface of the liquid in the pipet to the mark by carefully manipulating the screw. This device may be used for (1) poisonous liquids, (2) solutions of volatile gases like NH3, SOs etc., (3) large pipets which cannot be filled conveniently by suction.

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