1000 would become in a century 4776, and would double in 44,3 years.
The population of Cornwall being in 1831, according to the actual census, 301,017, if it continued to increase accordingly for a century at the rate ascertained between 1811 and 1821, the number of people in 1931 would amount to one million six hundred and eighty-eight thousand six hundred and fifty!
A Table exhibiting the amount to which the population of a thousand persons would amount in a century, and also the time of its doubling for each 5 per cent. of increase in 30 years, the period given for each parish from the Parliamentary Return.
| A thousand, with the following increase, in thirty years | Will become in a century | Will double in |
| 5 per cent. increase in thirty years | 1176 | 426 years. |
| 10 per cent. | 1374 | 218 |
| 15 per cent. | 1593 | 148 |
| 20 per cent. | 1836 | 114 |
| 25 per cent. | 2104 | 93,2 |
| 30 per cent. | 2398 | 79,2 |
| 35 per cent. | 2719 | 69,3 |
| 40 per cent. | 3070 | 61,8 |
| 45 per cent. | 3451 | 56 |
| 50 per cent. | 3863 | 51,3 |
| 55 per cent | 4310 | 47,4 |
| 60 per cent. | 4791 | 44,2 |
| 65 per cent. | 5308 | 41,5 |
| 70 per cent. | 5874 | 39,2 |
| 75 per cent. | 6458 | 37,2 |
| 80 per cent. | 7094 | 35,4 |
| 85 per cent. | 7773 | 33,8 |
| 90 per cent. | 8495 | 32,4 |
| 95 per cent. | 9264 | 31,1 |
| 100 per cent. | 10080 | 30 |
APPENDIX.
III.
The Editor has been favoured with the following list of plants illustrative of the mild climate of Cornwall.
The native plant of greatest curiosity is the Erica Vagans, Erica Didima of Withering, Erica Multiflora of Ray and Hudson. This plant spreads over the whole serpentine formation of the Lizard, and observes its limits almost to a foot. It is said to appear again at Clickitor near Liskeard, where the serpentine formation is also found.
The Ligusticum Cornubiense, remarkable only from its extreme rarity, grows near Bodmin, in a place called Margaret’s Wood.