20 BULLETIN 300, U. S. DEPARTMENT OF AGRICULTURE. 
This evidence was considered sufficiently complete with regard to the oxycellulose 
question. The behavior of Epicampes pulp with the usual solvents of cellulose was 
tried, with results as follows: 
(a) Schweitzer's reagent dissolved all but the merest faint trace of the fiber. 
(6) Concentrated sulphuric acid dissolved the fiber quite rapidly and completely, 
with a very faint darkening in color — not nearly so dark as straw celluloses usually 
give with sulphuric acid. 
(c) Zinc chlorid in concentrated hydrochloric acid dissolved the fiber more slowly 
than did sulphuric acid, but quite completely. 
(d) Zinc chlorid solution swelled the fiber, but dissolved it only slowly. 
The percentages of ash and moisture were also determined, ash being 2.2 per cent 
and moisture 4.8 per cent. Both determinations are of minor importance, the ash 
qualitatively and quantitatively being dependent on the previous treatment of the 
pulp and the moisture on the atmospheric conditions. The fact that they were not 
extraordinary had, however, to be determined. The moisture was within 0.2 per 
cent of that of poplar pulp under the same atmospheric conditions, indicating again 
the close chemical relationship that has been evident throughout in the comparison 
of poplar and Epicampes pulps, as it is well known that different forms of cellulose 
have widely differing hygroscopicity. It is, in fact, more closely related to poplar 
pulp than it is to straw celluloses, like those of wheat or rye. These latter give from 
12 to 14 per cent of furfural, for example, while Epicampes pulp gave a 10.8 per cent 
average, poplar giving 10 per cent. The resistance of Epicampes cellulose to destruc- 
tive agents in general is correspondingly higher than that of the usual straw celluloses. 
It was next intended to make a methoxyl determination on the Epicampes pulp, 
but microscopic examination showed (1) lignified cells still present and (2) cells in 
bundles that are usually completely separated by cooking, although only a very little 
of either. A methoxyl determination would be unfair to the sample when thus under- 
cooked, and so was not earned out. 
Direct determination of cellulose by any of the accepted methods is obviously use- 
less here, (1) because the pulp has already been through processes for lignin removal 
and (2) because the presence of oxycellulose renders impossible a determination of 
cellulose accurate to 15 per cent, as it is always attacked much more than lignin by 
the usual reagents. There is no existing accurate method for these conditions. 
Carbon and hydrogen determination by combustion would add, perhaps, a little 
to the already present wealth of evidence of oxycellulose presence, but the relation 
of furfural yield to carbon percentage is so well known that the carbon could be pre- 
dicted to a fraction of a per cent. This determination, therefore, seemed needless 
for the complete characterization of the Epicampes fiber. 
Hydralcellulose was tested for during the ' 'copper number' ' determinations, by 
Schwalbe's method, and found absent. 
To sum up the net result of these determinations: Epicampes macroura bleached 
pulp is a natural oxycellulose closely related to poplar pulp in chemical properties 
and considerably superior to the usual straw celluloses in power of resisting chemical 
attack by destructive agencies. 
SEMICOMMERCIAL TESTS OF THE PULP. 
Having experimentally determined the cooking conditions and 
found them to be reasonable and satisfactory and also having deter- 
mined that the chemical nature of the pulp was satisfactory, the 
work was continued on a semicommercial scale and was planned to 
include the actual manufacture of paper. There is a tendency on 
the part of many to discount the practical value of results obtained 
