disastrous results which would otherwise be inevitable.

[Footnote 1: For this improvement Prof. Swenson obtained a patent
Oct. 11, 1887, the grant of which was recently made the subject
of congressional inquiry.]

Immediately after it is drawn from the diffusion battery the juice is
taken from the measuring tanks into the defecating tanks or pans. These
are large, deep vessels, provided with copper steam coils in the bottom
for the purpose of heating the juice. Sufficient milk of lime is added
here to nearly or quite neutralize the acids in the juice, the test
being made with litmus paper. The juice is brought to the boiling point,
and as much of the scum is removed as can be taken quickly. The scum is
returned to the diffusion cells, and the juice is sent by a pump to the
top of the building, where it is boiled and thoroughly skimmed. These
skimmings are also returned to the diffusion cells.

This method of disposing of the skimmings was suggested by Mr.
Parkinson. It is better than the old plan of throwing them away to
decompose and create a stench about the factory. Probably a better
method would be to pass these skimmings through some sort of filter, or,
perhaps better still, to filter the juice and avoid all skimming. After
this last skimming the juice is ready to be boiled down to a thin sirup
in


THE DOUBLE EFFECT EVAPORATORS.

These consist of two large closed pans provided within with steam pipes
of copper, whereby the liquid is heated. They are also connected with