6 FUMIGATION METHODS 



invitation, Mr. Coquillett took his apparatus to the 

 orchards of A. D. Bishop, and commenced a new series 

 of tests. The ones giving the best results were the 

 same as some of Mr. Coquillett's earliest experiments, 

 in which the gas was generated in a simple generator 

 beneath the tent, according to the formula now gen- 

 erally used. 



It was generally believed by Mr. Coquillett at this 

 time that it was the aclinic rays rather than the heat 

 rays of the sun that injured the foliage. It had been 

 previously noticed that trees were more injured during 

 the middle of the day than at other times, and it 

 was usually attributed to the heat. Working on his 

 theory, Mr. Coquillett began experiments with a 

 black tent, and confirmed his belief that it was the 

 aclinic and not the heat rays that caused the trouble. 

 Naturally, night work in fumigation soon followed. 

 It was on Mr. Bishop's place where the first practical 

 night fumigation was inaugurated. The success of 

 these experiments has been far-reaching. The adop- 

 tion of methods here perfected has been quite univer- 

 sal. In practical results, the fumigation at night is 

 satisfactory and regarded as essential to good fumiga- 

 tion in citrous orchards. Mr. Bishop, in company 

 with some neighbors, applied for a patent on the proc- 

 ess, which was granted, even in the face of a strong 

 protest from Mr. Coquillett and Dr. Riley to the Com- 

 missioner of Patents. L/ater, however, the courts de- 

 cided that the process was not patentable, and the 

 controversy ended. 



The main interests centering around fumigation 

 were confined mainly to California until 1893. ^ n 



