a soft substance and crumble like damp sugar; while other
pieces are found quite hard, and of a shining, foliated appearance;
or else opaque and resembling a piece of burnt allum. It often
happens that both these forms are found in the same mass. Pieces
which are taken up whilst soft soon become hard by keeping; and
they are never known to continue long in a soft state, as far as I
have been able to learn."

He records that it is not found at all above the Falls, in the greatest
amounts in the Gorge, close to the Falls; and in decreasing quantities
as the distance from them increases; and is never found at a greater
distance from them than perhaps a mile. From several scientific
experiments which he made upon this substance, he deduced,

"1st, That this concrete is not an alkaline earth, as it is not
affected either by the vitriolic or vegetable acids.

"2d, That we may, with more probability, say that it is a
combination of an acid with a calcareous earth, and that it might
with propriety be ranked amongst the selenites."

He thought it was formed by the moisture arising from the Falls
constantly and slowly filtering between the layers of rock, in whose
crevices it deposited its heavier portions, and that the violent
agitation which the water had undergone disposed it to part with its
earth more easily than it would otherwise do.

He adds, "The circumstance of this Spray not being found above the
Falls seems to suggest an opinion that that part of the vapor which
hangs upon the surrounding rocks is the heaviest, as being most
loaded with earthy particles, whilst the remainder which mounts up
is the purest and contains little or no earth."

Dewit Clinton, when he visited Niagara in 1810--as a Member of the
first Board of Commissioners, appointed by the State of New York, to
report on the whole subject of the proposed Erie Canal, noted in his
diary,

"A beautiful white substance is found at the bottom of the Falls;
supposed by some to be Gypsum, and by the vulgar, to be a
concretion of foam, generated by the forces of the Cataract. But it
is unquestionably part of the limestone, dissolved and re-united."

Since Clinton's time no attention has been paid to this substance as a
curative agent.

As a geological substance it is still collected, but with greater ease
than formerly, for, besides being found on and below the face of the
cl