June, 1912
T H E JOURAVAL OF ILYD U S T R I A L AND ENGIiVEERILVG C H E J I I S T R Y .
sulphuric acid for drying purposes. The storage bottle for hydrochloric acid should be not less than thirtysix inches higher than the flask.
453
an amateur glass-blower, the parts are all stock articles. -4 is an ordinary ice-water tank, B and D go-liter earthenware filter cylinders, C a I j-liter glass bottle, and E a filter flask. It is regulated by a deVice of Ostwald,I already found efficient on a smaller scale. Sulphuric acid, previously diluted in A with 6 parts of water, flows from I3 through glass and rubber connections by way of C into D , which contains ferrous sulphide. The gas thus generated passes through the upper outlet of E to the piping of the laboratory. When the supply exceeds the demand the excess gas stores itself under pressure in C by displacement of acid into B , a t the same time stopping
B J
-
0 Y
Ey means of the thistle headed funnel, the lower part of which is drawn out to not more than I/,@ inch diameter, commercial hydrochloric acid is delivered to the bottom of the flask containing concentrated sulphuric acid. The advantages of this apparatus are that hydrochloric acid gas is evolved immediatell- after turning on the acid. C h turning off the acid, the evolution of gas ceases within a few seconds. A steady flow of gas can be maintained for long periods of time with practicnl1~-no attention. Unless the loner portion of the thistle-headed funnel is drawn oyt as described above, the apparatus will not n-ork in a satisfactory manner. The dran-n out portion should commence above the sulphuric :wid in the flask. ?‘he above apparatus has been in use for some time and has given great satisfaction. DEPARTMEKT, DAVIS & CO.,
-4SALYTICAL
P.\RICE, DETROIT, I f I C H .
TWO PIECES OF LABORATORY APPARATUS. B y HAROLD CAXNING CHAPIN.
Received January 29, 1912.
T h e hJ-drogen sulfide generator here illustrated has been in use in this laboratory for more than two years, supplying classes of over 1 7 j men. For an apparatus of its capacity it is simple, inexpensive, and requires but little personal attention. With the exception of the iron clamps securing the cylinder heads, and glass gauges and connections which can be put together by
I
generation until it is itself exhausted. The flask E catches and renders visible the overflow in case D fills with spent liquor. Its lower cock serves to admit air and relieve suction when liquor is drawn off through the cock on I?. To prevent small pieces of sulfide from clogging this last outlet a layer of brick is placed in the bottom of the cylinder, and to aid distribution of the acid an inverted dish is laid on top of the sulfide. The acid reservoir B is placed horizontally to lessen fluctuations in the gas pressure, which is dependent upon the difference in level of the contents of B and C. The connections between 12. uiial.
Chem , 31, 183 11892).
454
T H E JOCR.I-.-IL OF I N D U S T R I A L A N D E N G I N E E R I X G C H E M I S T R 1 7 .
the cylinders and their covers, which are ground to fit one another, are made tight with soft paraffine. Another apparatus, exceedingly simple but so efficient as to merit brief description, is a glass siphon for emptying carboys. It has a t its delivery end a cock of the diameter of the tube, and a t the bend a smaller cock through which it can be exhausted. n’hile one arm is being sucked full of acid from the carboy the other is by the same operation exhausted, so that if the tube be of large diameter the liquid having reached the summit trickles over and fills the siphon completely.
June. 1 9 1 2
the cup, made of heavy spun copper with a I / / flange a t the top, measures 3 3 / / inside diameter, and is 3 Sfr deep, To the point of supply, .I,/,’’ above the hot-
\VALKERLABOKATOKY. RENSSELAER POLYTECHNIC INSTITUTE.
UNIQUE WATER BLATH. B y S. W. WILES. Received February 15, 1912.
In comniercial laboratories where a large amount of work is carried on and time is an important factor, the chemist has found i t necessary to devise and construct time-saving apparatus. We have designed a rapid heating steam bath that combines several practical and economical features. The bath is made of heavy copper supported on a braced stand of I” angle iron. The top of the bath measures 2j” by 14%”, and is supported on the under side by a triangular copper stripping to prevent sagging; it contains twelve 3%’’ holes, and two j3il4’’ holes, fitted with porcelain rings. The bath proper is 2’’ deep a t the outside edge, and the bottom makes an angle of 30’ with the horizontal, reaching a depth of 4‘‘ a t the center. To the center of the bottom is riveted a threaded ring, soldered to make a tight joint. A collar fits over a cup and when connected to the threaded ring makes a water-tight joint;
I
tom, it contains 2 5 0 cc. The cup is fed by I/~‘’ brass. pipe connected by means of a riveted shoulder and soldered to make a tight joint. The feed pipe is connected to a constant supply T1::ater Level Rey~ilator of the latest pattern. As is often the case with municipal water supplies. the pressure is freakish and the result is the burning out of expensive m-ater baths. In this type of bath the only portion affected is the spun cqpper cup, which costs but a small sum and can be replaced in a few minutes. The bath just described. gives a full head of steam within three minutes, and a uniform distribution throughout the entire bath. One has been used daily for a year and a half in our laboratory, and has given the utmost satisfaction. From the standpoint of economy and upkeep, the writer feels that this type of bath may be found to be of value in other lahoratories besides our own. 1,ABORATORY O F
WILEY& COMPANY, BALTIMORE.
ADDRESSES OCCUPATIONAL POISONING IN CHEMICAL TRADES.
I
observed of six diseases, namely, poisoning by Lead, mercury, arsenic and phosphorus, together with anthrax (or wool-sorters’ disease) and the caisson In this brief discussion of the Occupational or In- disease. In January, 1912,a sub-committee for the industrial Diseases connected with the chemical trades, vestigation of occupational diseases was appointed either in the production, manufacture or application by the i’iew York State Branch of the American Asof chemical substances, the following subdivisions of sociation for Labor Legislation. This committee, the topic will be considered: mainly through a salaried investigator, has already I. To what extent do such diseases prevail in Xew gathered many interesting facts. I n the past few York City? years isolated reports have appeared in medical pub11. To what extent are such diseases fatal or in- lications on the diseases under discussion, a number of capacitating ? which have been made by members of my Medical 111. What measures should be undertaken t o mitigate Clinic Staff in the Dispensary of the Cornell Univeror prevent the manifold evils of the occupational sity Medical College and Bellevue Hospital, where w e disease hazards? meet annually with many thousands of workers in I . Prevalence.-Only within a very short time has all manner of trades. The latter institution. espeany effort been made to secure accurate data bearing cially, affords perhaps as large a n experience or‘ this upon this phase of the question. I n September, 1911, type as may be met with anywhere in this country. a law became operative requiring physicians to re- I n the absence of extensive published data, some port to the New York State Labor Bureau all cases reference to my personal experience may be permitted, Read before the New York Section of the American Chemical Society, derived mainly in the two institutions mentioned March 8 . 1912. by Dr. Thompson, Professor of JIedicine in the Cornel1 Cniand in the wards of the Presbyterian Hospital I n versitv Medical College in Xeti York City. B y W.GILMAXTHOMPSON. Received March 19, 1912.
