Feb., 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 A LARGE FAT EXTRACTOR By CARLI,. A. SCHMIDT
Received December 11, 1915
Nearly all the types of fat extractors which have been described have been designed for the purpose of quantitatively determining fat in some particular substance rather than merely freeing a substance of its fat content so t h a t the fat-free residuum may be used. The quantitative determination of fat can usually be made on a comparatively small sample and for such purposes the various types of fat extrac-
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all connections, thus preventihg any leakage of ether vapor. I n addition t o its use in extracting fat from several pounds of material, the apparatus may be used in the recovery of the ether used in the extraction and it is even adapted for the distillation of anhydrous ether. The extraction apparatus consists essentially of two parts, a large glass distilling flask, F , and the extractor A B , the latter made of heavy glass. The upper part, A , of the extractor, fits into a groove, V , which can be filled with mercury, thus insuring an ethertight seal. The other joints, 1, m , %, 0 , are likewise made ether-tight. by means of mercury seals. The material t o be extracted is put in a large, hardened filter paper shaped into a bag and placed in B , the bottom of the bag resting on a small porcelain filter plate. Vapor from the boiling ether in F will pass through the tube E and be condensed a t A , dripping on the substance in B . When the ether in B has reached the height of the tube H it will siphon back into the flask F , provided a small constriction be made in the glass tube a t P. The ether used in the extraction may be recovered by distilling into B and draining through the stopcock S. I t may be of advantage t o insert a glass siphon into the flask F which will eliminate the trouble of disconnecting the flask to remove the fatty residuum. Action of ether on the corks 1, m, n may be prevented by coating them with gelatine or glue. RUDOLPH SPRECKELS PHYSIOLOGICAL LABORATORY UNIVERSITY OF CALIFORNIA.
BERKELEY
SIMPLE SODIUM LAMP FOR POLARISCOPE B y G. K. FORESMAN Received December 30, 1915
W FATEXTRACTING APPARATW
(l/s
ACTUALSIZE)
tors on the market are well adapted. B u t when the fat from several pounds of material must b e extracted, as is generally the case in the preparation of vegetable proteins, in order t o obtain even a comparatively small yield of protein, recourse is generally had to some home-made type of fat extraction apparatus, since there are no extractors on the market adapted for this particular purpose. Benson and Thompson1 have described an extractor used by them in extracting tannin from sawdust. A somewhat similar apparatus was used by C. H. McCharles, of this University, for the extraction of fat from vegetable substances used in the preparation of pure proteins. I have made an extractor similar in principle by using a filtering bell jar and the top of a vacuum desiccator, both having ground glass joints. But a ground glass joint, even when clamped, will not prevent leakage of ether vapor. The apparatus described below has mercury seals a t Beiison and Thompson, THISJOURNAL, 7 (1915). 916.
Special lamps t o produce a sodium flame for polariscopes are all expensive and more or less troublesome t o adjust and maintain in working order. A simple, cheap and satisfactory substitute is here suggested. It consists of a piece of fire- and acid-proof asbestos board about 4 in. square and '/B in. thick, with a slit 3 x 1 / 4 in. and I in. from the edge, cut in the asbestos. This is used in connection with an ordinary Bunsen burner with wing-top. The asbestos board is supported about in. above the wing-top by means of a burette clamp, the burner being directly under the middle of the slit and parallel t o it. The flame burns around the edges of the slit, forming a broad double flame which is easy t o locate with the instrument and of greater intensity than the usual flame. Salt is added around the edge of the slit as a saturated solution, by means of a pipette. The sides of the asbestos board may be bound with metal t o support it a t the ends of the slit. When one slit burns out another may be cut in the same piece of asbestos board, back of the first. The asbestos does not seem t o affect the quality of the sodium flame. CHEMICAL LABORATORY, PURDUE UNIVERSITY LAFAYETTE, INDIANA
