104 



ridge for two, three, or even four days, the Wood River oil would 

 sink into the ground almost at once. 



Later explanations from the responsible chemists brought out the 

 fact that the two refineries were supplied with crude oil from different 

 oil-fields, that furnished the Whiting refinery making a thick and 

 viscid road oil and the other a comparatively fluid and penetrating 

 one. Owing to this difference, indeed, the Wood River oil is much 

 used for road-making, for which the oil must penetrate and consoli- 

 date, as it dries, the surface layers of earth on the road; while the 

 Whiting product, lacking this quality of penetration, is virtually use- 

 less as a road oil. These facts were known, of course, to the Standard 

 Oil officials, but their bearing on our work was not appreciated ; and 

 they were unknown to us until the almost total failure of field opera- 

 tions called for an explanation. The Oil Company furnishing this oil 

 readily returned to purchasers all sums received for it, but this of 

 course did not compensate for the losses due to dependence on it as a 

 protection against the chinch-bug. 



Crude Creosote as a Repellent. — By a lucky accident another sub- 

 stance had been found in 1912 nearly as effective against the chinch- 

 bug as road oils of the best grade, costing more but requiring less 

 labor to prepare a path, and obtainable at any time and in any quan- 

 tity. A Montgomery county farmer, Mr. Henry Niehaus, who had ex- 

 hausted his supply of coal-tar in trying to protect his corn against 

 chinch-bugs coming from his wheat at harvest-time, was unable to 

 get more at Litchfield, but was given for trial some oil of creosote 

 from a barrel on hand in the general store of Bartling and Hussey, 

 with the remark that it was the "worst-smelling stuff they had ever 

 handled" and that "it ought to stop chinch-bugs, or anything else." 

 Poured along the coal-tar lines, it proved as effective as the coal-tar, 

 and was used for the rest of the season by Mr. Niehaus and by five of 

 his neighbors also. The facts coming to the knowledge of Mr. Flint 

 (my field assistant for that part of the state) in May, 1913, experi- 

 ments were at once made which showed that the chinch-bugs were 

 strongly held in check by the odorous vapors given off by the creo- 

 sote, and not by any caustic or other physical property. Indeed bugs 

 sur rounded by a circular belt of creosote on the ground would cross 

 it quickly when excited and without the slightest injury; but if it 

 were placed as a line across their path they would stop short of its 

 margin and turn in another direction. Enough was done with this 

 substance during the latter part of the season of 1913 to warrant us 

 in giving it equal standing with the petroleum road-oils — preferable 

 indeed in some respects — and this was the material with which the 

 final, most extensive, and most successful campaign of our chinch-bug 

 period was mainly made in 1914. 



The fluid creosote did not lie upon the surface but sank readily into 

 the ground, slowly evaporating on exposure, and it was necessary to 



