THE SMOKE NUISANCE. 477 
covered in total darkness, the telephonist began speaking into his instrument, 
and the illuminating spark was flashed upon the points. This operation was 
repeated with more than twenty plates in succession. The resulting negatives, 
on being developed, proved a triumph in two arts and a science. The photo- 
graphs printed from them showed under the glass, in some, contact of the points, 
and in others a variety of infinitesimally differenced intervals between them. 
Not one of the impressions had more than the one-twenty-four thousandth of a 
second in which to be begun and ended. — Electrical Review. 
-CHEMISTRY AND METALLURGY. 
THE SMOKE NUISANCE. 
PROF. R. S. G. PATON. 
In walking in and around Kansas City I have noticed a considerable amount 
of smoke emanating from the chimneys of a number of manufacturing establish- 
ments. This is by no means necessary, and should be checked at once, espec- 
ially in such a growing city, as the evil will in nowise become less on the increase 
of the number of chimneys. Smoke is deleterious to the health of a community 
and, besides, it is extravagance on the part of the manufacturers to allow of its 
emission. 
Whilst chemist of the Health Department of Chicago, I was given charge of 
the enforcement of the "Smoke Ordinance," and the following is some of the 
results of my work. 
This ordinance came into effect on the ist of May, 1881, and I had the 
honor to be appointed to carry out its provisions on the ist of July of the same 
year. From that date until the i6th of July, 1882, I acted alone; since then I 
have had either one or two assistants. 
The number of persons or firms called upon . , . ." 654 
The number of visits made 182 1 
The number of locomotives observed smoking ... 94 
The number of steam tugs observed smoking . . . 239 
The number of elevators observed smoking .... 18 
The number of special trips on locomotives .... 3 
The number of special trips on tugs 2 
The number of visits examining devices 63 
The number of abatements observed 219 
The number of devices for suppression of the nuisance 
examined , 49 
The number of suits commenced in 
