742 PROCEEDINGS OF SECTION H. 



felt, and precisely among'st, those who oeonpy the rooms or 

 buildings exposed to those influences in one way or another, 

 and we find that the attacks cease to occur when the defects 

 are repaired. But evidence on a large scale for the impor- 

 tance of this etiological factor in the production of typhoid is 

 furnished by the lowering of the typhoid sick-rate and death- 

 rate in towns, through attention to tlie cleansing of feecal 

 matters from the streets, the houses, and the soil, and through 

 an efficiently carried-out system of drainage and sewerage." 



Believing then, as I firmly do, that the pollution of the 

 subsoil is the main, I will not say the only, factor in the 

 etiology of typhoid in Hobart, I cannot help rejoicing at the 

 near establishment of a system of underground drainage by 

 the Metro])olitan Drainage Board recently constituted by 

 Act of ParHament. And I trust that before this Association 

 next holds a meeting in llobart the whole system will have 

 been perfected and carried out. This will be a double boon ; 

 it will provide for our present needs by a water-carriage 

 system, and it will atone for our jiast ignorance and misdeeds 

 l>y opening up and draining and aerating our polluted soil. 

 During the progress of the work fever of a typho- mala rial 

 type may be rife, but in the end benefit must accrue, and 

 typhoid, instead of a perennial resident as it now appears to 

 be, become a very occasional visitor. 



In alluding to the etiology of typhoid, I must not omit to 

 notice one factor to which special attention has already been 

 drawn in Hobart. When typhoid assumed an epidemic and 

 virulent type throughout the Austrahan colonies during the 

 year 1887, our eminent Statist, Mr. R. M. Johnston, read a 

 paper before the Royal Society of Tasmania, in which he 

 attributed the epidemic variations of typhoid to the operations 

 of three great causes — (1) Local hygiene, (2) Seasonal in- 

 fluence, (3) Cosmical influence. With the first of these 

 causes, local hygiene, as modified somewhat by the second, 

 seasonal influence, rainfall, &c., I have been principally con- 

 cerned in these notes ; and as to the third, cosmical influence, 

 Mr. Johnston expressed his belief that such super-terrestrial 

 phenomena as the spots on the sun are calculated to intensify 

 typhoid epidemics and increase the death-rate. 



