1858.] OF THE HOUSE OF DELEGATES.          217

with the marks to indicate the quality of each. This table is
so constructed, that the purchaser may readily ascertain its
commercial value, as compared with hone phosphate of lime,
estimating the phosphoric acid as equal to the per centum of
that combination of lime and phosphoric acid, as indicated by
the letter in the table.

1. COLOMBIAN GUANO.

This is comparatively a new article. It is found deposited
on a group of islands called "The Monks," located in the
Caribbean sea. It is imported in large irregular stone colored
masses, very hard and brittle, and of great specific gravity.
It is prepared for market by being ground, when it forms a
fawn colored powder, a barrel of which weighs 400 lbs. It is
remarkably rich in phosphoric acid in combination with lime.

TABLE FOR PHOSPHATIC GUANO.

"Colombian."

All Guano marked "Columbian," letter A, contains phos-
phoric acid equal to from 80 to 90 per cent, of B. P. L.

All Guano marked "Colombian," letter B, contains phos-
phoric acid equal to from 70 to 80 per cent, of B. P. L.

"White Mexican Guano."

All Guano marked " White Mexican," letter A, contains
phosphoric acid equal to from 70 to 80 per cent, of bone phos-
phate of lime.

All Guano marked "White Mexican," letter B, contains
phosphoric acid equal to from 60 to 70 per cent.

"Mexican Guano."

All Guano marked "Mexican," letters A. A., contains phos-
phoric acid equal to over 55 per cent, of bone phosphate of
lime.

All Guano marked "Mexican," letter A, contains phos-
phoric acid equal to from 45 to 55 per cent.

All Guano marked "Mexican," letter B, contains phos-
phoric acid equal to from 35 to 45 per cent.

All Guano marked "Mexican," letter C, contains phos-
phoric acid equal to from 25 to 35 per cent.

All Guano marked "Mexican," letter D, contains phos-
phoric acid equal to from 15 to 25 per cent.

El Roque Guano."
All Guano marked "El Roque," letter A, contains over