449 
preéminent in this interesting field of chemical research. The principal 
scheme of analysis used by these chemists is briefly, as follows: 
IVLOIStULG === ae 2 Ifygroscopic water, or water of condition. 
Loss on drying at 100° C. 
NG) Aire Foch ede Total residue left on ignition. 
Hydrolysis (a) ~--_- Loss of weight on boiling raw fiber five 
minutes in | per cent solution of caustic 
soda, 
Hydrolysis (b) _---.Loss of weight on continuing to boil one 
hour. 
Cellulose_________... White or bleached residue from following 
treatment: (1) Boiling in 1 per cent solu- 
tion of caustic soda five minutes; (2) 
exposing to chlorine gas one hour; (3) 
boiling in basic sodium sulphite, 2 per 
cent solution. 
Separate portion 
taken for each 
determination, 
(Results calcu- - 
lated in per- 
Mercerizing ___ ____ Loss on treating one hour with 33 per cent 
centage of dry : 3 
solution of caustic soda, cold. 
substance. ) = : a : : 
NILTAON: 232s me Weight of nitrated product obtained by 
treatment with a mixture of equal vol- 
umes of nitric and sulphuric acids one 
hour in the cold. 
Acid purification ___Raw fiber boiled one minute with acetic 
acid (20 per cent) washed with alcohol 
and dried. 
Carbon percentage. .Determined by combustion. 
This method of study is of value in that it gives results which are 
dependent upon definite properties of the fiber substance, but it is more 
extended than is required for special or more practical purposes, there- 
fore it has been restricted to our wants and also modified in some 
respects. 
Joisture—As is well known, all celluloses under normal conditions 
contain a certain amount of moisture which is termed “water of condi- 
tion,” which is quite definite for each fiber, although it varies within 
limits which are dependent upon the hygrometrie state of the atmosphere. 
It is characteristic of abacd waste that it readily absorbs moisture and 
in an ordinarily dry condition holds from 11 to 13 per cent, but during 
the rainy months the water content was found to reach a maximum of 
18 per cent. This hygroscopic moisture is a factor of some importance 
in the buying and selling of fibrous substances either in the raw state 
or as paper pulp. It is customary to decide on some arbitrary percentage 
as representing the moisture normally present. The standard used 
varies with different countries and with different kinds of material. 
With wood-pulp, in which there is considerable commerce, 10 per cent 
is usually taken as representing the moisture normally present. 
N 
