Page:Transactions of the Provincial Medical and Surgical Association, volume 2.djvu/162

 life, than in the agricultural, a fact which can only be explained by the general law of increased mortality, at all ages, which seems to obtain in all manufacturing and crowded communities. Thus, at the 30th year, the proportion of the population is as follows:─Mining, 4870; agricultural, 5174. At the 60th year, the disproportion is still greater, and, of course, still against the mining population, the number in the mining parishes being 2700, while in the agricultural it is 3422.

3. It is seen by Tables XVI. and XVII. that, by the 60th year, the whole number of the mining population has become so reduced, that, from this age upwards, the annual number of deaths is greater in the agricultural class. Thus, from Table XX. it appears that at the 70th year, the proportional number of survivors, in the two classes, is as follows: in the agricultural, 2359; in the mining, 1667; and between this and the 90th year, (a period of 20 years,) there occur no less than 669 more deaths in the former than in the latter. This shows that previously to the 70th year, all the increased mortality that depended on mining, has disappeared for want of subjects, leaving the survivors to be influenced by the natural causes of decay only.

4. The powerful influence of the occupation of the miner in shortening his life, is further illustrated in a very satisfactory manner, by Table XVIII. which gives the proportion of the deaths, in the two sexes above their 80th year, in the two classes of persons. Every one is aware of the superior longevity of the female sex, in all countries, and under almost all circumstances. In countries where the