802 DR R. E. SCORESBY- JACKSON 



and to which such effect might altogether or in part be due : a task which is not 

 very readily accomplished. Again, we cannot, if we would attain a rigid accu- 

 racy, attribute fluctuations in the death-rate to vicissitudes of weather, until we 

 obtain a uniform climate over the entire area of observation, and this we shall 

 never acquire. It may perhaps be objected to the results of my investigations, 

 that it is not fair to apply the average of the climate of all Scotland to the death- 

 rate of the eight larger towns ; that the towns have a climate distinct from that 

 of the rural and insular districts, and that each town has one of its own. That 

 is quite true ; but it is an objection which may with equal propriety be urged 

 against the application of the climate of any large town to the mortality of its 

 several parishes, the particular climate of each of which may, and often does, 

 differ from that of its neighbour. But I prefer to consider the town districts 

 alone, because it is in them that we meet with the mass of disease and the 

 multiplied mortality ; and as to the applicability of the general climate to a local 

 death-rate, we may regard it in this w^ay, that the climate of the towns is a 

 climate within a climate, and that, whatever difference there may be between the 

 containing and the contained, any modification of the larger must in a corre- 

 sponding manner affect, if not in degree, at least in kind, the smaller. 



Another objection might suggest itself in the returns of the cause of death 

 made to the Registrar-General. It may be said that many of these returns 

 are, at least, inexact ; as, for example, when it is stated that death was caused 

 by dropsy, the accumulation of fluid being merely a symptom of the real dis- 

 order : or, where the certificate tells only half the truth, as when a person who 

 is dying of one disease is accidentally cut off by an intercurrent attack of another 

 kind which would not have proved fatal but for the moribund condition of the 

 patient at the time when it took possession of him ; in such a case one class of 

 disease is robbed of a victim which another gains by an adventitious circum- 

 stance. These and many other objections might be raised against investigations 

 into the influence of the weather if we would be satisfied with nothing short of 

 logical exactness ; but we may undoubtedly arrive at an approximate knowledge 

 of its effects if we are careful to avoid error in the main features of the inquiry. 



The influence of external causes upon the constitutions of living creatures 

 varies with locality, the variety depending upon the character of the causes, 

 whether individually or combined. In a general way, these causes may be classed 

 into two leading groups, as in the following order : — 



A. Unitersal Causes, affecting Nations, as, — 



1. Position of a Country relative to — The Equator — water in motion (e.^,, the sea with its 



currents ; rivers, springs, extensive lakes) — stagnant waters (e.g., canals, shallow 

 lakes, marshes) — mountains, forests, arid plains, fields of ice. 



2. Aspect of a Country. — General elevation and configuration, geological structure, physical 



and chemical properties of its soil, state of cultivation. 



3. Atmospheric Phenomena. — Temperature, barometric pressure, direction and force of 



winds, humidity, insolation. 





