ted here to
the proportions of the architecture, there could be nothing gained by
surveying the transcript, that could not be gained by surveying the
originals. In this little brown drawing, however, the truth is truth
according to the rules of lineal perspective, unerringly deduced; and
from a set of similar drawings, this art of perspective, so important
to the artist--which has been so variously taught, and in which so many
masters have failed--could be more surely acquired than by any other
means. Of all the many treatises yet written on the subject, one of the
best was produced by the celebrated Ferguson the astronomer, the sole
fruit derived to the fine arts by his twenty years' application to
painting. There are, however, some of his rules arbitrary in their
application, and the propriety of which he has not even attempted to
demonstrate. Here, for the first time, on this square of paper, have
we the data on which perspective may be rendered a certain science. We
have but to apply our compasses and rules in order to discover the
proportions in which, according to their distances, objects diminish.
Mark these columns, for instance. One line prolonged in the line of
their architrave, and another line prolonged in the line of their
bases, bisect one another in the point of sight fixed in the distant
horizon; and in this one important point we find all the other
parallel lines of the building converging. The fact, though unknown to
the ancients, has been long familiar to the artists of comparatively
modern times,--so familiar, indeed, that it forms one of the first
lessons of the drawing-master. The rule is a fixed one; but there is
another rule equally important, not yet fixed,--that rule of proportion
by which to determine the breadth which a certain extent of frontage
between these converging lines should occupy. The principle on which
the horizontal lines converge is already known, but the principle on
which the vertical lines cut these at certain determinate distances
is not yet known. It is easy taking the _latitudes_ of the art, if we
may so speak, but its _longitudes_ are still to discover. At length,
however, have we the lines of discovery indicated: in the architectural
drawings of the calotype the perspective is that of nature itself;
and to arrive at just conclusions, we have but to measure and compare,
and ascertain proportions. One result of the discovery of the
calotype will be, we doubt not, the produc