of the lungs and kindred affections. ‘It is, however, probable that the figures representing the mortality are fairly accurate, as the errors are to a certain extent compensating; and, indeed, tubercles are often found even in the diseases above mentioned.’[99]

[99] Dr Wynter Blyth.

The following table, taken from the Registrar-General’s returns for 1848-75, shows the annual number of deaths in England from phthisis, during a period of 28 years:—

184851,663
184950,299
185046,618
185149,166
185250,594
185354,918
185451,284
185552,290
185648,950
185750,106
185850,442
185950,149
186051,024
186151,930
186250,962
186351,072
186453,046
186553,734
186655,714
186755,042
186851,423
186952,270
187054,231
187153,376
187252,589
187351,355
187449,379
187552,943

Dr Farr in his letter to the Registrar-General on the causes of death in England in 1875, writes, “Phthisis is a most fatal disease, although it has declined within the last twenty-five years.”

According to the same authority, the mean rate of mortality from this disease was 2·811 per 1000 in the five years from 1850 to 1854, and 2·283 in the five years from 1870 to 1874.

One of the most prominent facts revealed even by a cursory study of the statistics of phthisis, is the large share which the breathing of impure or tainted air has in the origin and dissemination of the disease.

Hence it follows that thickly populated and overcrowded localities suffer much more from its ravages than those which are less densely inhabited. This is exemplified in the following table:

—

Density of Persons to a Sq. Mile.Proximity or nearness of Person to Person.Average Annual Mortality to 100,000 living.
Phthisis.Other diseases of the Respiratory Organs.
Yards.15 to 2525 to 3535 to 4515 to 2525 to 3535 to 45
Healthy districts135163336398330344567
London19,470142643954934569148
Lancashire1,008604194754844686195
England and Wales3081083624384073861113