square the timber, and follow out faithfully the working plan placed
in their hands. But the architect must know much more than this; he
must be acquainted with the principles of proportion and form; he must
know the laws which regulate the distribution of heat, light, and air,
in order that he may give to each part of a complicated structure its
due share of these advantages, and combine the multifarious details
into a consistent whole. Take again the case of the seaman. It is
enough for the steersman that he watch certain symptoms in the sky and
on the waves; that he note the shifting of the wind and compass, and
attend to certain precise rules which have been given him for his
guidance. But the master of the ship, if he be fit for his
situation--and I am sorry to say that many undertake the duties of
that responsible office who are not fit for it--must be thoroughly
acquainted, not only with the map of the earth and heavens, but he
must know also all that science has revealed of some of the most
subtle of the operations of nature; he must understand, as far as man
can yet discover them, what are the laws which regulate the movements
of the currents, the direction of the tempest, and the meanderings of
the magnetic fluid. Or, to take a case with which you are more
familiar--that of the merchant. The merchant's clerk must understand
book-keeping and double-entry, and know how to arrange every item of
the account under its proper head, and how to balance the whole
correctly. But the head of the establishment must be acquainted, in
addition to this, with the laws which regulate the exchanges, with the
principles that affect the production and distribution of national
wealth, and therefore with those social and political causes which are
ever and anon at work to disturb calculations, which would have been
accurate enough for quiet times, but which are insufficient for
others. I think, therefore, that I have established the truth of the
proposition, that men who aspire to exercise a directing and