[FROM OUR SPECIAL BOSTON CORRESPONDENT.]

BOSTON, May 8th, 1870.

We Bostonians are greatly surprised that your valuable journal has as
yet taken no notice of the great undertaking of the century--the Cape
Cod Canal. However, you New-Yorkers are quite out of the world, and
unless you read the Boston _Transcript_ regularly, can not be expected
to know much about the enterprises with which the earnest men of the
nation are occupied. The great Cape Cod Canal is, however, not meant
simply for the benefit of the Bostonian nation, but for the commerce of
the civilized world. It is destined to work a more important revolution
in the trade of Plymouth, Barnstable, and Nantucket, than the Suez or
Darien Canals.

Of course you are familiar with the peculiar conformation of Cape Cod.
It juts out into the Atlantic like an immense elbow, and, indeed, is
understood to be modelled after the brawny arm of the gallant CHARLES
SUMNER. Vessels passing between ports on the western and those on the
southern coast of Massachusetts, are now obliged to make a wide _detour_
in order to circumnavigate the Cape. It is now proposed to cut a canal
across the Cape just where it juts out from the mainland, and thus avoid
the tedious circumnavigation. The enormous importance of this work will
be at once perceived. The Canal will be nearly four miles in length, and
will be made of a uniform width of four feet, with a depth of two. This
gigantic undertaking will of course cost an immense amount of time and
money, but under the able supervision of ELKANAH HOPKINS, the gifted
engineer who constructed the board-walk in front of Deacon BREWSTER'S
house, at Standish Four Corners, there can be no doubt of its success.