106 EIGHTH EVENING.

“ Is it not,” said his father, “ that there is a great
deal more knowledge in one than in the other P”’

“ To be sure it is,” said Charles.

Father, Would it not, think you, be as impossible
for any number of men, untaught, by their utmost
efforts, to build and navigate such a ship as we have
seen, as to fly through the air ?

Charles. I suppose it would. |

fa, That we may be the more sensible of this, let
us consider how many arts and professions are neces-
sary for this pucpose. Come—youa shall begin to
name them, and if you forget any, I will put you in
mind. What is the first ?

Ch. The ship-carpenter, I think.

Ha, True—what does he do ?

Ch. He builds the ship.

fa. How is that done ?

Ch. By fastening the planks and beams together.

fa. But do you suppose he can do this as a common
carpenter or joiner makes a box or set of shelves ?

Ch. I do not know.

4a. Do you not think that such a vast bulk requires
a great deal of contrivance to bring it into shape, and
fit it for all its purposes P

Ch. Yes.

fa, Some ships, you have heard, sail quicker than
others—some bear storms better—some carry more
lading—some draw less water—and so on. You do
not suppose all these things are left to chance ?

Ch. No.

a. In order with certainty to produce these effects,
it is necessary to study proportions very exactly, and
to lay down an accurate scale, by mathematical lines
and figures, after which to build the snip. Much has
been written upon this subject, and nice ealeulations
have been made of the resistance a ship meets with in
making way through the water, and the best means of
overcoming it; also of the action of the wind on the
sails, and their action in pushing on the ship by means