average on each year. If we take the rainfall upon the last six months, July to December inclusive, of the five years, reduced to the mean for a month, we find a large falling off for the last three years; thus—
| Millimetres. | ||||
|---|---|---|---|---|
| 1853 | 94.32 | mean fall per month | ||
| 1854 | 105.44 | ,, | ||
| 1855 | 64.13 | ,, | ||
| Earthquake in | October, | 1856 | 77.47 | ,, |
| ,, | December, | 1857 | 74.05 | ,, |
But if we look at the table, we shall see that the deficiency prior to the shock of October, 1856, was still more remarkable; for during the four preceding months up to the 1st of October, 1856, only 95·9 inches of rain fell altogether, and there was none at all in June. The last six months of 1857 were actually dryer than those of 1856, in the ratio of 74 to 7712; and if we compare the total rainfall of 18 months, from 1st July, 1856, to the end of 1857, with that for the corresponding 18 months, 1st July, 1853, to the end of 1854, we find the numbers are—
| Inches. | ||
|---|---|---|
| Eighteen months ending December, | 1854 = | 1563.67 |
| ,, ,, | 1857 = | 1447.45 |
| Difference | 116.22 |
Again, in 1857, November and December were both unusually dry, but the latter month, which is that of our earthquake, unprecedentedly so; the rainfall for this month only being for the five years—
