on Pcnnanent Meadoic Land. 
After this digestion, the whole was diluted with hot water, 
filtered, and the insoluble matter well washed with hot water. 
At this stage the product retained several per cent, of nitrogenous 
substance, and a considerable amount of otiier matters which were 
dissolved in the next step of the process. The substance was 
removed from the filter, and then boiled for half an hour with 
600 septems of very dilute caustic soda. The whole was again 
thrown on a filter and well washed with hot water. A drop of 
sulphuric acid was, however, added to the wash-water after the 
main portion of the washings had passed off ; and the washing 
was continued until the water no longer came through acid. 
The matter was then Avashed from the filter, dried, and weighed 
as icoody Jihre. After this treatment, the product still retained 
0"1 per cent., or less, of its weight of nitrogenous substance, and 
some mineral matter ; both of which were determined and de- 
ducted by calculation. 
The individual determinations of this \yoody-fibre are given for 
reference in Table VHI. in the Appendix: and an examination 
of them will show within what limits the duplicate or triplicate 
results agree with one another. It is believed that the figures 
are probably very trustworthy as a comparative series, comparing 
specimen with specimen as to the respective amounts of Woody- 
fibre of a given degree of insolubility or induration; but they are 
pretty certainly too low considered as including the whole of the 
cellulose. At least jNIr. Segelcke found that even Swedish filtering 
paper was somewhat reduced in amount by the second part of 
the process, namely, the treatment with alkali, though it was not 
so by the digestion with the sulphuric acid. On the other hand, 
with any less treatment with the alkali, not only higher results, 
but inconstant duplicates or triplicates, w'ere obtained ; and the 
product at the same time retained a considerably higher amount 
of nitrogenous substance. 
As already intimated, the v.oody fibre was only determined in 
the hay of certain plots, namely, those selected for the botanical 
separations referred to in Part III. It was, however, determined 
in the produce of those plots, in each of the three years of 
the experiments. We are enabled, therefore, to trace the 
effects of both season and manwing on the percentage of the 
best is, 1 volume of oil of vitriol to 16 volumes of ^vater ; the temperature that 
of the boiling point ; and the time of action a quarter of an hour. A great practical 
advantage of substituting the use of a stronger acid, and a temperature below 
the boiling point, by a weaker acid and the boiling point, is the ease by which 
constancy in the latter temperature can be secured. Indeed, the discrepancies, 
such as they are, between the duplicate and triplicate determinations recorded in 
the Appendix, Table VIII., Mr. Segelcke attributes mainly to the accidental 
fluctuations in practice, somewhat above or below his then adopted tempei-atui-e 
oflSO^F. 
