The yellow line is drawn on the same principle, and represents the imports for the same years; the difference between the two, which is stained green, being the balance for or against England.
Thus, for example, we see that, till the year 1775, the exports rose very fast, and were far above the imports, but that then their proportion begun =sic= to vary; insomuch that, in 1781, the yellow line rose above the red, when the balance in favour of England turned against it, to the amount of a million for one year. In 1782, the balance again became favourable; but, though the trade was increasing, the balance was once more, in 1785, against England; ever since which it has been more or less in our favour.
The difference between the two lines is stained pale green, when the balance was favourable, but of a pale red when against England.
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The advantages proposed by this mode of representing matters are the same that maps and plans have over descriptions, and dimensions written in figures; and the same accuracy is in one case as the other; for, whatever quantities can be expressed in numbers may be represented by lines; and, where proportional progression is the business, what the eye does in an instant, would otherwise require much time.
The impression is not only simple, but it is as lasting in retaining as it is easy in receiving. Such are the advantages claimed for the invention twenty years ago, when it first appeared; the claim has been allowed by many, and not objected to, so far as the inventor knows, either in this or in any other country.
EXPLANATION OF PLATE NO. IV.
Chart of revenue, from the time of Queen Elizabeth to the present day.
Till the accession of William III. in 1688, the materials for this are not altogether accurate; but they are not far wrong, and indeed, the low state of the revenue, previous to that period, is such that it is a matter of little importance whether or not they are very exact. It is represented here rather as a contrast to the present high revenue, and a matter of curiosity, than as being of much importance.
The pale red part expresses the free revenue, or what is over, after paying the interest of our debt.