ctice of dissection was introduced
on a large scale. That of the cadaver of an elephant occupied several
sessions, and was of such interest that the monarch himself was a
spectator.

To the same epoch with the formation and first work of these two bodies
belongs the invention of a mathematical method which in its importance
to the advance of exact science may be classed with the invention of
the alphabet in its relation to the progress of society at large. The
use of algebraic symbols to represent quantities had its origin before
the commencement of the new era, and gradually grew into a highly
developed form during the first two centuries of that era. But this
method could represent quantities only as fixed. It is true that the
elasticity inherent in the use of such symbols permitted of their being
applied to any and every quantity; yet, in any one application, the
quantity was considered as fixed and definite. But most of the
magnitudes of nature are in a state of continual variation; indeed,
since all motion is variation, the latter is a universal characteristic
of all phenomena. No serious advance could be made in the application
of algebraic language to the expression of physical phenomena until it
could be so extended as to express variation in quantities, as well as
the quantities themselves. This extension, worked out independently by
Newton and Leibnitz, may be classed as the most fruitful of conceptions
in exact science. With it the way was opened for the unimpeded and
continually accelerated progress of the last two centuries.

The feature of this period which has the closest relation to the
purpose of our coming together is the seemingly unending subdivision of
knowledge into specialties, many of which are becoming so minute and so
isolated that they seem to have no interest for any but their few
pursuers. Happily science itself has afforded a corrective for its own
tendency in this direction. The careful thinker will see that in these
seemingly diverging branches common elements and common principles are
coming more and more to light. There is an increasing recognition of
methods of research, and of deduction, which are common to large
branches, or to the whole of science. We are more and more recognizing
the principle that progress in knowledge implies its reduction to more
exact forms, and the expression of its ideas in language more or less
mathematical. The problem before the organizers of this Congres