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JOURNAL OF THE PLYMOUTH INSTITUTION. 
Smith), and to its relative composition at different elevations, &c. 
Man's body in these regions, exists more fully in relation to those 
physical existences and forces, which are inseparable parts, indeed, 
of life and being. 
Analogy. — We may know by observation and analogy the condi- 
tions, or laws so-called, of Phthisis, and thus be on the method of 
prevention, long before we may have learnt the rates, order, and 
periods of vital being, or of the parts, limbs, or segments of animal 
forms. In the history of knowledge, analogy is a method equally 
or more pregnant than experiment even. 
Out-of-door Life. — In other countries lessened Phthisis goes along 
with greater out-of-door life ; e.g. as, at any rate, one cause, in the 
races of Central Asia ; in negroes in the great deltas of Guiana, 
those who are field labourers are free from Phthisis, whilst those 
who become clerks, schoolmasters, &c, die much of Phthisis. The 
mean annual death-rate for ten years, 1864-74, in the colony of 
Victoria, was 12*04 for 10,000 of the mean population, whilst for 
the city and suburbs of Melbourne itself, it was 21 *23 per 10,000. In 
England and Wales it was 25.47 per 10,000. (Mr. H. H. Hayter's 
Notes on Victoria.) There is in these instances indication of a 
generalization, where it is seen that out-of-door life, in climates so 
different as those of Dartmoor, 50° N. lat., Guiana, 6° K lat., the 
dry, hot regions of Victoria and the Cape Colony, 30° to 35° S. lat., 
in Central Asia, in latitude 30° to 40° N. lat., have lessened 
Phthisis. On the other hand, town life in England increases the 
death-rate. London life diverts the natural law of women dying 
in excess of men ; it having a mean of 3*35 for men, against 2*39 
for women. The one condition common to such varied climates 
and races, is freedom from Phthisis, with out-of-door life. 
Some known conditions under which Phthisis appears. — Wet soil 
(Dr. Bowditch, Boston, U.S.); irritating substances in the air, in 
some trades ; monotonous indoor life, in some sisterhoods of nuns ; 
children going to bed cold ; indoor life, &c. (The question of food 
is not entered into in this lecture.) 
Some other known Preventives. — Ague regions ; e.g. Wisbeach, 
in the Pens, has a mean death-rate from Phthisis of 1*48 only, to 
2-47 in England and Wales. 
Some facts of the Natural History of Phthisis. — It is a too early 
(relatively to other parts, limbs or segments,) failure of nerve or vital 
formative power, of those segments of the animal, of which the lungs 
