166 <> TAsseMBny 
centimeters long, and two centimeters in diameter. In the bottom of 
this tube is placed a small tuft of ignited asbestos, and over this is 
poured a little asbestos pulp. By means of an adapter and a filter 
pump the filter is washed repeatedly with water till the washings are 
clear, and is then thoroughly dried. Two or three grams of substance 
are weighed i in the tube, which is placed in a fat extractor, similar to 
that described by Professor Caldwell in the second report of the Cor- 
nell University Experiment Station, and the substance exhausted with 
ether. The ether extract is dried at 100° C., and weighed in a tared 
flask. 
A tuft of clean cotton is kept in the bottom of the fat extractor to 
arrest any loose fibers of asbestos that may escape from the filter. The 
extracts thus obtained have been uniformly clear. 
5. Crude fiber. 
The tube containing the fat-free substance, in the preceding sec- 
tion, is placed for a short time in the drying oven to remove the ad- _ 
hering ether. The substance, together with the asbestos composing 
the filter, is then transferred to a beaker of about 500 c.c. capacity, the 
small particles of substance adhering to the tube being washed into 
the beaker with a little water. Fifty c.c. of a five per cent solution of 
sulphuric acid and water enough to make the volume 200 c.c. are 
added to the contents of the beaker which is heated to boiling, and 
kept at that temperature for thirty minutes. Care must be taken to 
prevent the liquid boiling over when ebuljtion first begins; after 
the boiling has continued a short time it will proceed quietly. 7 
While the boiling is in progress a filter is prepared by placing a tuft 
of ignited asbestos, supported by a small platinum cone, in the throat 
of a funnel of about 200 c.c. capacity, and ponrae a little asbestos 
pulp over it. 
The filter may be washed with water till no asbestos is soparated, if 
desired, but this is not necessary as none of the substance will pass 
through, if the filter is properly prepared. When sufficiently boiled, 
the contents of the beaker are allowed to settle for a moment, and the 
liquid poured upon the filter, leaving the solid substance, as much as 
possible, in the beaker., The filtration is conducted without pressure 
as the substance often becomes so compact uvon the filter when pres- 
sure is applied that it greatly hinders the flow of the liquid. The sub- 
stance in the beaker is washed three or four times, by decantation, 
with hot water, pouring the liquid through the filter. The washing 
is greatly facilitated by the use of the filter pamp. When washed the 
substance in the funnel together with the asbestos filter is returned to 
the beaker. Twoand five-tenths grams of potassium hydrate, in solu- 
tion, and water enough to make the volume 200 c.c are added, and the 
whole is then boiled for thirty minutes. After the boiling, with the 
alkali, has continued for a few moments there is a tendency to bump. 
The bumping is sometimes so scvere that the boiling cannot be safely — 
continued over the lamp, in such cases the beaker is removed to the 
steam bath, and kept at 100° C. till the expiration of the time. The 
contents of the beaker are then filtered through a ‘‘ Gooch crucible,” 
without the aid of the pump, washed with hot water, then with alco- 
hol, and finally with ether. It is then thoroughly dried and weighed, 
after which it is ignited and weighed again. ‘The difference between 
the two weights gives the crude fiber. : 
