Appendix B.: On the Connection Between the Irish Population and the Rate of Mortality in Towns.

I have tested the suggestions made in the text in a variety of ways, and have, in almost every case, met with confirmatory evidence.

In calculating the percentage of Irish population in any town, I have taken the numbers only of the population of twenty years of age and upwards, for the obvious reason that if an Irish family live for a few years in England, they may have children registered as English born, although they live under the same sanitary conditions as their Irish parents.

The following statement compares the proportion of Irish population with the mortality in some of the principal towns:

The high mortality of Liverpool and Manchester is here in striking conformity with the large Irish population, and more recent returns of the Salford mortality would also exhibit conformity. Sheffield is the only serious exception.

In another calculation, I took a list of the mortality of eighteen English towns in the year of the census of 1861. I separated the towns into three groups, according as the mortality was:

1. At the rate of 28 or more per 1,000.

2. Between the rates of 24 and 26.

3. At the rate of 24 or less.

The percentage of Irish population in the aggregate of each group, and the average mortality, were then found to be as follows:

With the above we may compare London, which has an Irish population of 5·7 per cent., and a mortality of 23·6, on the average of the years 1851–60.

Observing in another list that Altrincham, Bakewell, and Warwick were districts of low mortality, the rate scarcely exceeding 20 in 1,000, I calculated the Irish percentage as follows:

Or, aggregating the three towns together, we find the Irish population to be on the whole 2·2 per cent., or less than half the average proportion of Irish throughout England and Wales, which is 4·52 per cent.

These facts appeared to me to be almost of a conclusive character by themselves, but in extending the comparison to the Scotch towns, we meet with the strongest possible corroboration. The eight principal Scotch towns happen to fall apart into two very distinct groups, the particulars of which are shown in the following table:

Forming averages of the above numbers, we have:

It may not be unworthy of remark that in the most unhealthy towns—Liverpool, Manchester, Salford, etc.—the Irish women are in excess of the men; whereas in the most healthy towns—such as Hull, Leith, and Aberdeen—the women are even fewer than the men. The following is the proportion of Irish women to the whole number of women in the healthy places:

We should naturally turn to ascertain whether the mortality in Ireland at all bears out the apparent effect of Irish immigration in England. Taking the average of a few years of the returns of births and deaths in Dublin, I find that the rates are in both cases almost exactly the same, namely, 26·1 per 1,000. In one return the deaths were 33·6, while the births were only 24·7. As the birth-rate much exceeds the death-rate in England and other progressive countries, we must either regard the population of Ireland as being in a very abnormal state, or we must reject the returns as wholly unworthy of confidence.

The Editor of The Statistical Journal has often appended a note to the Irish returns, calling attention to their apparent untrustworthiness. Until we know to what extent the returns are defective, they are simply misleading and mischievous; but if they are at all approximate to the truth, they lend strong support to the supposition that English mortality is greatly influenced by Irish immigrants.