1911 - 12 .] 
211 
The Sun as a Fog Producer. 
Prevention of Sun Fogs. 
In previous papers I have frequently referred to the great nucleus- 
producing powers of the products of the combustion of sulphur. The 
conclusions then arrived at seem to be here confirmed — namely, that these 
products are one of the principal causes of haze, and of the dense fogs of 
large cities and great manufacturing centres ; that they play no mean 
second part along with smoke in these phenomena. At present the import- 
ance of these products from burning sulphur does not seem to receive 
anything like the attention it requires. Though smoke-abatement societies 
are everywhere active at the present time, yet no attention is given to the 
invisible products of the sulphur in the coal. Now, no one would disparage 
the efforts of these societies to reduce the smoke which casts a pall over our 
cities and manufacturing centres ; yet this investigation points to the 
fact that even if they succeeded in stopping all smoke, the atmosphere would 
still be densely hazed in all conditions, and thickly fogged when the air 
was damp. The task of getting rid of the sulphur products is not so simple 
as that of getting quit of the smoke. Of course, one can easily in imagina- 
tion make conditions in which both smoke and sulphur products would be 
kept out of the atmosphere. If we were only allowed to use gas in our 
fires, and all the gas were purified from sulphur, etc., then we might look 
for a purified air. It would, however, be necessary for the retorts, or what- 
ever was used for distilling the coal, to be heated with purified gas, and 
the resultant coke of the retorts made into water-gas and purified, as coke 
contains a great deal of sulphur, which is oxidised and passes over with the 
other gases. Any such treatment of our coal, however, seems for the 
present to be outside practical engineering, and the remedy for the condi- 
tion of our atmosphere would appear in the meantime to be rather hopeless. 
Most of the undesirable conditions of life, however, are yielding to patient 
investigation, and there seems no reason why this one should not at least 
be mitigated, if the subject were taken up by some institution or body of 
investigators interested in the subject. So far as one can see, the chemist 
is the one likely to indicate the line of research. For instance, can he not 
tell us of some substance which when burned with coal will combine with 
the sulphur products and prevent their escape into the atmosphere — some- 
thing that will give more promise of success than the lime treatment ? That 
idea is merely suggested because it seems to be the simplest and the least 
likely to rub against our conservative ways of doing things ; and unless the 
substance was very expensive, the country would not object to an Act of 
