302 ON THE JUICE OF THE SUGAR-CANE. 
Juice 
Of White Bellognet Cane. Of Penang Cane. 
1st Pressure. 2nd Pressure. 1st Pressure. 2nd Pressure. 
Density . . . 1084 1079 1080 1078 
Quantity of sugar .. 19*8 18'9 19*6 18.5)? 
Albuminous matters . 0-18 0-27 0-16 0.20 > g 
Weight of ashes . . 0-20 0-22 0*13 0.23 ) S- 
The difference is more marked with the Penang cane, than with the 
white Bellognet, resulting from the former being harder, and offering 
more resistance to the pressure of the cylinders. 
After what has been said, an account may easily be given of the 
numerous specialities which take place in sugar manufacture, and 
which have been explained in various ways. It is evident at once that 
the juice extracted from canes slightly crushed being relatively richer 
in saccharine and poorer in organic and mineral substances, is of easier 
labour, and yields for trie same weight or volume, a greater proportion 
of sugar. Such a result is not solely due to a superior saccharine richness- 
of juice, but rather to a less quantity of albumenoid and saline princi- 
ples ; for by our usual process of manufacture, evaporation cannot be 
prolonged without producing a very perceptible interversion of crystal- 
lisable sugar, and this transformation is also subordinate to the 
quantity ol organic matter held in the juice. 
It seems to me incontestable that it is still more in this difference of 
qualities presented by the juice, according to the pressure to which the 
cane has been subjected, that we ought to seek for a rational explanation 
of the general belief that with the same means of evaporation, the extrac- 
tion of sugar was easier formerly than now. If it be remembered that 
the first advance realised was due to the use of more perfect mills, and 
that the evaporating apparatus now employed was only adopted long 
after, it will be difficult, unless we deny the results of exact experi- 
ments, and these too within the reach of all, not to attribute to the more 
efficacious pressure of our mills, what in my opinion, has been most 
erroneously considered as the result of degeneration of the cane. 
I shall show further on in continuing these researches, that this idea 
is contrary to the facts which come under our daily notice, and shall 
complete my remarks on the part which this assumed degeneration plays 
in the production of sugar. 
(To he continued.) 
