, 1875-03-03

examination of those interested 10 the sugar
cane industry.
The difficulties attendant upon making on a
sugar estate an experiment involving the e-
act determination of weights and denslties are
80 great that no surprise will be occasloned to
those familiar with tropical sugar culture If
even serious. errors creep in. In the record
of the experiments you have published, the
quantity of detail furnished is an evidence of
the desire to give the public the means Of
checking the calculations, and indeed, those
who know Mr.. Russell, even by reputation,
will be satisfied that bis authentication IS a
guarantee for good faith. Errors of method
or record may nevertheless exist, and propose
to examine the figures contained in the report,
and shall be glad if this should elicit a reply
from Mr.. Russell.
The report describes Zone of the many trials
made on a large scale" This is therefore a
selected experiment, and may be considered
a satisfactory one and consistent with the other
numerous experiments.
We are told that 1918 lbs. of canes yielded
$3.50 lbs. of juice at 9'5oB, or 66'4l per cent.
Therefore, the megass must have weighed
1924 lbs, or have been 1850 per cent. Of the
weight Of canes.
We are told that the canes operated on con-
tanned 1917 per cent. of woody fibre.
Therefore, the unexpresscd juice must have
been (33. 59-15.77} II 50 per cent. of the
weight of the canes.
The weight Of the unexpressed juice was
1890 lbs.
for as $3.50 {: 1852 1924 1890
We are informed that 300 gallons of water
are added to the wet megass therefore, to
1890 lbs ofcane juice at 9'5oB, 1000 lbs. of
water at Dob we're added. The 1890 lbs. of
juice we're retained by 1884 lbs Of woody fibre.
If the water were intimately and perfectly
blended with the megass SO that the con-
tents Of every cell were partially displaced
and the remaining portion was mixed with its
due proportion of water a condition of things
which, without much mechanical agitation or
the proloDgation of the treatment over an ade-
quate time is clearly impossible the mixture
would indicate a density Of about Blob, for
as 1890 1890 :95: 81.
Thus FOB is the maximum land indeed
the practically impossible) density of the second
squeezings. But we have been told that the
second squeezings gagged COB, VAicA IS in
possible.
The second squeezing removed 207 gallons
or 2159 lbs, of diluted juice. The weight Of
the original megass was 1924 lbs. and this was
increased by the addition of 5000 lbs. of wa
ter to 1924 lbs. The removal by second pres
sure of $3.50 lbs. of weak juice should have
left finished. megass weighing 2465 lbs. But
2O24 lbs. only were found, and a loss Of 44l
lbs. had taken place. The gentlemen who made
the experiment consider that the GLOSS is ac-
counted for by the great evaporation which takes
place during the different landings" Let US
proceed to examine whether, if this theory were
correct, the increased density of the juice could
raise the second squeezings to COB, on which
all the calculations of profit are based. If
the loss Of megass had been that Of water con-
verted into vapour, there would have been
practically only 2000-441=l559 lbs. of water
associated with the juice left in the megqsS
In this case, 1896 lbs. of juice would have been
mixed with 1859 lbs. of water;
AS 2949 139O::9'5 43.
Thus the maximum density would have been
4'3oB, and this increased density of six-tenths
of a degree does not help US materially.
Let US consider if it be possible that AL lbs,
of water could pass away in vapour. Even if
the diluted juice stood at tho boiling point of
water, the removal of AL lbs. of water would
abstract 426 ,447 units of heat, or Sufficient
to reduce the temperature 0f2,369 lbs. Of BOIL
smg mater to freezing point!!
Therefore evaporation does not account for
the reduced weight of the megass.
It is thus seen that very much more sugar
must of necessity be left in the megass than
the 9 IS per cent. of sugar referred to in the
report, but whether the amount be greater or
less, it is incorrect to say "that it may all be
taken out by a slight addition of water and
A.