36 SECOND REPORT OF THE STATE ENTOMOLOGIST. 



for killing museum pests, was suggested in 1840. Placed in insect boxes, 

 it kills acari and psoci, but not other museum pests. Experiments 

 were made with it against Phylloxera vitifolice in 1872. Fischer began 

 experimenting with it in 1881. It is a better insecticide and cheaper 

 in its crude form than when pure, but is more injurious to plants in that 

 form. It has been applied to grapevines by pouring a kilogram [2.20 

 pounds] of it in a trench from 15 to 20 cm. [6 to 8 inches] deep near 

 the stock of the vine and then filling the trench with earth. 



At a subsequent meeting (28th of December), Dr. T. Taylor stated 

 that rats, mice, crickets and locusts were driven away by the use of 

 naphthaline. Earth worms were driven out of the ground and killed by 

 placing it in the bottom of a flower-pot where they occurred. Insects 

 infesting seeds were killed by placing it in jars with the seeds, without 

 injury to the seeds. Moistening increases the efficacy of naphthaline 

 {Psyche, for January-February, 1884, iv, pp. 133-134). 



Kerosene Oil Emulsions. 

 In the preceding report of the Entomologist, reference was made 

 (page 44) to an emulsion of kerosene and milk, but no directions were 

 given for making it. The omission is here supplied. The method 

 recommended by Mr. H. G. Hubbard, a special agent of the U. S. De- 

 partment of Agriculture, seems to be the best presented. It is as fol- 

 lows: 



Take of refined kerosene two parts, fresh, or preferably sour 

 cow's milk, one part (percentage of oil 66|). Mix in a pail or tub, by 

 continuous pumping with a force-pump back into the same vessel 

 through the flexible hose and spray nozzle. After passing once or twice 

 through the pump the liquids unite and form a creamy emulsion, in 

 which finely divided particles of oil can be plainly detected. Continue 

 the pumping until the liquid curdles into a white and glistening butter, 

 perfectly homogeneous in texture and stable. The time required for 

 producing the butter varies with the temperature. At 60 Fahr. it will 

 be from one-half to three-quarters of an hour; at 75°, fifteen minutes; 

 and the process may be still more facilitated by heating the milk up to, 

 but not past, the boiling point. 



Upon standing for a day or two the milk (if sweet, has been used) 

 will curdle, but as it simply thickens and hardens without separating 

 from the oil, it needs only to be stirred, not churned again, to bring it 

 back to its former smoothness. If sour milk is used no fermentation en- 

 sues, and if not exposed to the air, the butter can be kept unchanged 

 for any length of time. 



When needed for use the butter will mix readily with any proportion 



