This is the operation which is to be measured; this is the mean
proportional by which we are to estimate the age of worlds that have
terminated, and the duration of those that are but beginning.
But how shall we measure the decrease of our land? Every revolution of
the globe wears away some part of some rock upon some coast; but the
quantity of that decrease, in that measured time, is not a measurable
thing. Instead of a revolution of the globe, let us take an age. The age
of man does no more in this estimate than a single year. He sees,
that the natural course of things is to wear away the coast, with the
attrition of the sand and stones upon the shore; but he cannot find a
measure for this quantity which shall correspond to time, in order to
form an estimate of the rate of this decrease.
But man is not confined to what he sees; he has the experience of former
men. Let us then go to the Romans and the Greeks in search of a measure
of our coasts, which we may compare with the present state of things.
Here, again, we are disappointed; their descriptions of the shores of
Greece and of Italy, and their works upon the coast, either give no
measure of a decrease, or are not accurate enough for such a purpose.
Pages:
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189