BULLETIN OF THE BUSSEY INSTITUTION. 453 
tained in the liquid that no tests could be made. It is noticeable 
that hydrochloric acid of 85% has no such power to break up 
the cellulose in wood as is exhibited constantly by strong sul- 
phurie acid. 
The residual wood left after the treatment with strong hyciro- 
chloric acid, and subsequent boiling with the 3% acid, was mixed 
thoroughly with 10 c.c. of strong sulphuric acid (90% H,SO,) 
and left at rest for 24 hours. The black, pasty mass was poured 
into enough boiling water to reduce the strength of the acid to 
3.5%, and the mixture was boiled for three hours. The filtered 
solution was neutralized with calcium carbonate and tested. It 
did not need to be decolorized. It gave quasi(a) D = 92°.9 and 
23.72% of sugar calculated as dextrose on the dry residue, — 
or 18.83% calculated on the dry wood. When this solution 
was evaporated and treated with cold, strong alcohol, the matter 
left undissolved gave quasi(a) D = 71°.60, and the portion soluble 
in alcohol gaye quasi(a) D = 54°.93. On again evaporating the 
aqueous solution of the matter not dissolved by alcohol and treat- 
ing the new residue with cold, strong alcohol,—%in order to 
dissolve out as much dextrose as might be possible, — there was 
obtained a new fraction insoluble in alcohol which, on being 
dissolved in water, gave quasi(a) D = 85°.88. There was not 
enough matter dissolved by the alcohol to admit of any critical 
examination, but the solution was set aside to evaporate, and 
after six months it was noticed that the solid residue had segre- 
gated in the form of isolated tufts or balls (presumably of dex- 
trose) rising from the centres of thin, starlike radiations of 
crystals. 
The second half of the filtrate from the hydrolysis with sul- 
phurie acid of 3% (after the action of strong sulphuric acid) was 
boiled three hours longer and examined as before. It did not 
need to be decolorized. That it had suffered considerable altera- 
tion was shown by the fact that it now gave quasi(a) D = 64°.49, 
and 28.27% of dextrose calculated on the dry residue, or 22.45% 
calculated on the dry wood. After evaporating to dryness and 
treating with cold, strong alcohol, the matter not readily dissolved 
in this liquid gave quasi(a) D = 58°.66, while the portion soluble 
in alcohol gave quasi(a) D = 49°.85, both calculated as dextrose. 
It should be said that most of these experiments with birch 
