492 



SCIENCE. 



[N. S. Vol. XIX. No. 482. 



incumbent on the owner or builder of every 

 new establislmient, where soft coal is to be 

 burned, to install the proper apparatus for 

 burning it smokelessly. It should be neces- 

 sary for such owner or builder to obtain 

 a permit for setting boilers or furnaces, 

 contingent on proper compliance with the 

 laws regarding smoke abatement, just as it 

 should be necessary to obtain a permit for 

 erecting a building in compliance with the 

 laws concerning safety against fire and 

 accident. This provision is not a hardship 

 and it inures as much to the benefit of the 

 owner as to that of the public. 



If every new furnace is thus set in a 

 proper manner and is under the inspection 

 of the proper officers, a rapid improvement 

 will take place. The old will in the nature 

 of things disappear; it is the new which 

 must be the more carefully watched. 



In dealing with establishments where 

 smoke is already in evidence both moral 

 and legal suasion must be employed; the 

 former when it will serve, the latter as a 

 final resort. Once convince a man that coal 

 will be saved when smoke is stopped, and 

 the battle is half won. The writer has a 

 record of scores of such bloodless victories. 



Before very much can be said to an of- 

 fender it is necessary to prove to him that 

 he is an offender, and this can only be done 

 by systematic observation covering some 

 little period of time. Whatever system is 

 adopted, the ratings of the various stacks 

 will depend largely on the judgment of the 

 observer and smoke charts are an vinneces- 

 sary incumbrance. Readings taken at in- 

 tervals of three or five minutes for several 

 hours, with a grading from one to four in 

 the scale of blackness, will give a fair rela- 

 tive showing for the various chimneys ob- 

 served and furnish a basis for arguments 

 with the various proprietors. 



An observer who has had experience can 

 rate twenty to thirty chimneys in this way 

 from a convenient vantage point. If 4 is 



taken as dense black smoke and as ab- 

 sence of smoke, a two-hour series of five- 

 minute readings, or twenty-five in all, will 

 give the percentage directly by summation. 

 These two-hour sets can be repeated at dif- 

 ferent times of day so as to cover the whole 

 period of daylight. In this way the in- 

 spector soon becomes thoroughly familiar 

 with each district and knows all the black 

 sheep. A fair comparison made from such 

 ratings will often shame the offenders into 

 better performance. 



In rating locomotives a diflierent method 

 must be adopted, as the time of observation 

 is rarely over two or three minutes. For 

 this work a graphic log has been found most 

 reliable. Heavy horizontal lines represent 

 per cent, of black smoke, while vertical 

 rulings represent time intervals, usually 

 from three to five minutes each. The ob- 

 server counts regularly as he watches the 

 stack and puts down at each interval of 

 time a dot on one of the horizontal lines 

 corresponding with the smoke at that in- 

 stant. A line drawn through these dots 

 shows plainly the variation in conditions. 

 The other data are filled in as far as they 

 can be ascertained and a copy of this report 

 (made in duplicate by the use of carbon 

 paper) is sent to the proper official of the 

 road immediately. This makes a record 

 which is rarely disputed by the engineer 

 or fireman. 



This system as applied in Cleveland had 

 the immediate effect of reducing the smoke 

 from locomotives to less than half the 

 former amount as a result of improved 

 firing, and there has been steady improve- 

 ment ever since. 



In dealing with the smoke problem where 

 the evil already has a firm foothold it is 

 necessary to institute at first an educational 

 campaign, showing the conditions as they 

 exist, the possibility of betterment and the 

 resulting economy. Most smoke-producers 

 are intelligent and reasonable men and will 



