BAIRD &TATLOCK (LONDON) LTD. 



B 



2555 A2555 2556 



2555 Fat Extraction Apparatus, by Dr. E. Drechsel, with mercury seal. 





2557 



2/6 



31- 



.\2555 Fat Extraction Apparatus (Greiner & Friedich's) . 

 Capacity of filter tube . . 



60 



31- 



i litre. 

 4/- each. 



100 



200 grammes. 

 5/6 each. 



2556 Extraction Thimbles of Fat-Free Paper, C. S. & S., No. 603. These extraction cups 

 of fat-free paper are for use with the Soxhlet extraction apparatus, Nos. 2548-2554. 

 Seamless, and made from the best filter paper material, it is absolutely impossible for 

 any particles of the substance undergoing extraction to find their way into the ether. 

 The ether itself flows readily from the shells, and the extraction is greatly facilitated. 



Packed in boxes, containing twenty-five thimbles. Cups can be used repeatedly. 



Length . . . . . . 60 80 80 80 90 94 



Diameter . . . . . . 26 22 30 33 19 33 



Per box of 25 .. ..5/3 5/3 5/9 5/9 5/3 7/3 



Suitable for . . . 30 60 100 



123 millimetres. 



43 

 11/3 



200 gramme Extractors. 



2557 Extraction Apparatus, new pattern, with three flasks, condenser and Soxhlet's extractor 

 all ground to fit . . . . . . . . . . . . . . per set 



A New Apparatus for Extracting Liquids. Hitherto all the usual types of apparatus for extraction of liquids 

 have very fragile spirals, are difficult to clean and if a large quantity of liquid is to be extracted, the extraction must 

 |be interrupted by changing the liquid. 



The apparatus avoids these disadvantages. This differs from the usual Soxhlet apparatus for extracting solids 

 only by the inner funnel-tube with a spiral- jacket, the inlet funnel and the higher opening of the syphon. 



The use of the apparatus is as follows : 



The apparatus is filled with the liquid up to near the syphon. Then by heating the flask filled with ether, etc., 

 <(<., the ether vaporizes and the vapour goes through the vapour-tube to the condenser as in the ordinary Soxhlet 

 apparatus. The condensate drops in the inner funnel-tube and rises in small drops following the thread of the 

 tunnel-jacket to the surface of the liquid. In this manner very good contact between the ether and the liquid to 



^tracted is obtained. The ether accumulates above the surface of the liquid until it syphons over and the 

 operation continues. Upon finishing the extraction, which can be ascertained by testing a small portion of the 

 liquid drawn off through the cock, the liquid is removed and a new portion added through the funnel without 

 taking the apparatus apart or interrupting the heating. 



The condenser is a new return-condenser with the principle of counter-currents. The essential feature of this 

 condenser is the spiral cooling tube. The condensate between it and the outside jacket forms a seal, compelling 

 the vapour to travel a spiral distance of 4 feet up through the condenser. To avoid heating the incoming cooling 

 water by the outgoing warm water the outlet tube is insulated by an air-jacket. This jacket is enlarged so as to 

 make the cooling water also take a spiral course exactly against the vapour. 



[Reprinted from The Jour/iM of the American Chemical Society. Vol. XXXIV. No. 3. March, 1912.] 



1 12 6 



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505 



