22 BULLETIN 1298, U. S. DEPARTMENT OF AGRICULTURE 
The deadhead log, No. 2556, contained a larger proportion of 
cellulose than did the sound wood. This condition is at least par- 
tially accounted for by the fact that it had been stored under water 
and the water-soluble material had been more completely removed. 
If the cellulose content of both samples be calculated on the basis of 
the residue after the removal of the hot-water-soluble portion, No. 
2556 gives a slightly lower value than VA. In any event, the con- 
clusion may be drawn that the log stored under water, and therefore 
out of contact with the air, had not suffered appreciable decay. 
The stability of the cellulose isolated by the Cross and Bevan 
method is greatly decreased as measured by the resistance to the 
action of 17.5 per cent NaOH. This resistance is indicated by the 
proportions of alpha, beta, and gamma cellulose. 
Both the cold-water-soluble and the hot-water-soluble content of 
these woods increased with increase in decay. 
An even greater indication of increasing decay is afforded by the 
increase in solubility of the wood in caustic soda. The results obtained 
with 7.14 per cent NaOH appear to differ from those obtained with 1 
per cent NaOH only in intensity. Even in wood which has not 
reached a sufficiently advanced stage of decay to be rejected for 
pulping, the solubility in 1 per cent NaOH has risen to 39.9 per cent, 
as compared with 8.8 per cent for sound wood. The copper number 
also increases with increased decay, but its changes during the earlier 
stages are not so pronounced. 
The process of decay does not appear to have destroyed the lignin. 
In fact, the proportion of lignin increased as decay advanced. This 
increase can readily be explained, however, without assuming the 
formation of lignin, provided it is assumed that an actual loss in 
weight of wood substance occurs during decay. In this way the 
lignin, unchanged in weight, represents a larger and larger proportion 
of the residual wood. The decrease in wood density, already referred 
to, and the action of isolated fungi, described later, fully substantiate 
the assumption. 
Pentosans showed a decrease and methyl pentosans an increase; 
but the significance of these changes is not yet clear. 
The resins, as determined by solubility in ether, and the mineral 
content, as determined by the ash, were not appreciably affected by 
the process of decay. 
ANALYSES OF MECHANICAL PULPS MADE FROM SOUND AND FROM DECAYED SPRUCE 
WOODS 
Mechanical pulps Nos. 1AA and 2AB, groimd respectively from 
sound wood No. 1 and decayed wood No. 2546, were chemically 
analyzed. The data are found in Table 8. The data for pulp No. 
1AA, Table 8, closely resemble those for sound wood VA in Table 7. 
The small difference becomes even less significant when note is taken 
of the low water solubility of the pulp, due to the removal of a large 
proportion of the water-soluble content during the pulping process. 
On the other hand, in a comparison of the respective data for pulp 
No. 2AB and wood No. 2546, the decrease in water solubility is not 
sufficient to account for the more significant decrease in copper num- 
ber, lignin, and solubility in NaOH, and for the increase in cellulose 
content. Ij account is taken, however, of the brashness and brittleness 
of the decayed wood and of the abnormal losses in the white water, it 
