JOURNAL OF CHEMICAL EDUCATION
2166
SEPTEMBER, 1930
It does not require a vacuum, an inert gas, or glass-blowing operations. Lengths of these tubes were cut such as would give one-tenth gram of sodium, and the hydrogen equivalent was determined with this quantity. To determine the hydrogen equivalent, a water-filled gas-measuring tube was inverted in a large crystallizing dish of water and the tube clamped into position on a ring stand. A three-inch length of rubber tubing was plugged a t one end and the cut length of sodium-filled tube slipped in a t the other. This was then manipulated under the gas-measuring tube and the hydrogen collected. A short piece of copper wire bent at right angles served to dislodge any bubbles that get caught in the tube and shut off the water. The following table gives the results obtained by four different teachers of our department, using the method as a lecture demonstration.
52.5 53 58.5 52.9 55.2 54.8
19.5 21.5 24 211 21 22
731.17 723.9 719.85 720. fi4 723.54 728.37 Average
47.2 46.75 50.8 45.8 48.8 48.6
23.6 23.8 21.5 24.27 23.14 22.9 23.3
This method has the merit of being rapid, easy in manipulation, and gives more accurate results than the old method of weighing the sodium directly. The tubes are easily filled and may be conveniently stored.
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Literature Cited FERNELIUS and SCHURMAN, "A Method for Showing the Metallic Luster of the Alkali Metals." J. C ~ ME.~ u c . 6, , 17654 (Oet., 1929).
Notebook of Early Manchester Chemist, Dr. W. Henry. Valuable facts about the work of Dr. W. Henry, the Manchester chemist, and a friend of John Dalton, have come t o light by the discovery of one of his old notebooks, which was recently saved from destruction by a furnace attendant a t the works of A. & S. Henry & Co., Ltd.. of Manchester, who found i t among some litter he had been instructed to burn. A paper on the subject was given a t a meeting of the Literary and Philosophical Society. Manchester, by Mr. W. Buckley. The notebook contains many of the laboratory records of experiments which Dr. Henry described in a paper read in 1818, entitled "Experiments on Gas from Coal, Chiefly with a View to Its Practical Application." The doctor was freauentlv asked his o~iniotlon ooints about the manufacture and use of coal gas a t the mills, and several of the entries in the notebook relate to the difficulties that arose and his exoeriments in connection with them. Among the h a 1 entries, which concerned experiments to be carried out a t a later date, is one suggesting the use of finely divided platinum for the analysis of gases by preferential combustion.-Chem. Age
