Nov., 1916
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y
I kg. of pulverized NaOH. When this has been well stirred in, add shredded asbestos gradually, continuing t h e stirring until t h e mixture no longer appears capable of wetting more asbestos. T h e whole mass is t h e n heated in a n air b a t h at 150 t o 180’ for 4 hrs. During t h e early part of t h e heating, additional quantities of asbestos are added from time t o time until i t presents t h e same appearance as before heating. After cooling, it is ground in a coffee mill until most of i t passes a Io-mesh sieve. A t u b e filled with this absorbe n t takes up 8 t o I O g. of carbon dioxide, corresponding t o 160 t o 2 4 0 carbon determinations, using the full factor weight on a steel containing 0 . 5 per cent carbon.
RESEARCH LABORATORY, MIDVALE STEELCOMPANY PHILADELPHIA
LABORATORY TABLE TOPS AGAIN By HILTON IRAJONES Received August 17, 1916
I039
boiling hot. Moreover, it is so poor a conductor of heat t h a t even thick glass containing hot liquids may be set upon i t without breaking. This does away with t h e use of suberite mats such as are required on stone, tile or glass tops. T h e asbestos slate t o p has everything t o commend it, a n d after four years of use I have yet t o discover a single fault. DAXOTA WESLEYAN UNIVERSITY MITCHELL, SOUTHDAKOTA
A SIMPLE MERCURY SEALED ETHER STILL By 0 . C SMITH A N D D. G. MORGAN Received June 27, 1916
T h e heater H was constructed from a sheet of galvanized iron and a n electric light socket fitted into t h e bottom. The corks which are inserted into t h e necks of the flasks a t D and E should be close-grained and fit tightly so as t o hold t h e mercury a t F and G. I t is not difficult t o make a mercury-tight fit if care is used in selecting t h e corks a n d t h e y are coated with a little vaseline before inserting. Before using, t h e flasks
Much has been written about various sorts of laboratory table tops-wood, alberene and tile advocates have all had their say. I n the past twenty years I have worked and condlucted classes on every sort of top-glass, tile, Cement, slate, alberene stone and wood. When I came t o Dakota Wesleyan I found a new one. Five years ago Dr. Sterling Temple, now of t h e University of Minnesota, installed t h e tables here. T h e tops are ordinary soft pine flooring on which is laid two sheets of t a r paper, and this is covered with large sheets of asbestos slate, two t o a table. I t is oneeighth inch in thickness. T h e asbestos slate is screwed on, t h e holes being counter-sunk and filled above t h e screw head with asbestos cement. The tables every year have been treated with a gasoline solution of paraffin concentrated enough so t h a t it would set t o a jelly consistency when cold. This solution is brushed on hot. We have found this method of paraffining much better and quicker than t h e old ironing in process. This paraffin treatment has given t h e tops a polished appearance b u t is really unnecessary a n d adds nothing t o their immediate serviceability or life. This asbestos top is so much better t h a n a n y other top I have ever seen t h a t I a m sure it would be extensively used if its advantages were more widely understood. It has low first cost, long life, and a n y one can u p u t i t on. I feel certain our table tops will be in good should be washed with ether t o remove the excess shape twenty years hence. They are fully. as good now as vaseline. The glass tubes A , B , C are about j , 5, I O when first installed. T h e asbestos top with t h e tar--.mm,, respectively, in diameter. T h e reflux condenser paper beneath it has elasticity, and 1 find there is I prevents the escape of ether, even less glassware broken on it t h a n on a wooden To r ~ m c v ethe ether f r o m the receiving flask J lift top. A1berene stone is Objectionable f o r u p t h e condenser I and insert a small siphon through A , beginners for this reason. T h e asbestos slate top is OgLAHoMA AGRICULTURAL EXPERIMENT STATIoli entirely unaffected b y acid or alkali even though STTLLWATER
i ADDRESSES A CENSUS OF THE ARTIFICIAL DYESTUFFS USED IN THE UNITED STATES‘ By THOMAS H. NORTON
The necessity for a complete enumeration of the artificial coloring matters, regularly consumed by the various manufac1 Address delivered before the American Chemical Society, a t the New York Meeting, during the Symposium on “ ~ Dyestuff~M ~ facture.”
turing industries of this country soon became evident when these branches were threatened in 1914by a dyestuff famine, as a result of the great European war. Those who took into careful consideration the possibility of creating a n independent American coal-tar dyestuff industry were obliged to study closely a number of factors bearing upon ~this ~ ~exceedingly ~i complicated ~
question. ~ ~ -4mong these were such items as the supply of crude materials, the chemists and
