362 



NAPHTHALEXE AS AN INSECTICIDE. 



Nai)hthalene is one of the by-products obtained in the distilhi- 

 tion of coal tar. It has been long known as an insect repellant, 

 and some of its uses are very famihar to nearly everyone. It may 

 be of interest, however, to bring together a brief account of sev- 

 eral different ways in which it may be employed. 



The best known use for naphthalene is for the protection of 

 stored clothing, books, insect collections, and museum specimens. 

 Clothing such as woolen garments, feathers, and furs are pro- 

 tected from moths and beetles by being packed in tight boxes, or 

 securely wrapped in parcels covered with paper, cotton, or linen 

 cloth. Moth balls, naphthalene flakes or crystals, freely used in 

 such boxes or parcels, give good protection, the insects being re- 

 pelled by the smell of the naphthalene. 



Fjooks which are kept in closed bookcases may be protected to a 

 large extent by scattering flaked naphthalene freely on the shelves, 

 behind the books, and o« and between the books themselves. 



Insect collections should be kept in tight boxes ; naphthalene 

 flakes in the bottom of the boxes, or moth balls on pins in the cor- 

 ners of each box, will keep out insects and mites which are de- 

 structive to stored insects. Moth balls can be fixed on pins quite 

 easily. An ordinary pin heated in the flame of a lamp or candle 

 can be forced through the moth ball by means of pliers or forcej^s, 

 and when it cools the naphthalene will set firmly round it. 



As a remedy to be used against cockroaches, naphthalene is not 

 so well known. In the Agricultural News for September 27, 1913, 

 a note appeared giving an account of good results obtained from 

 the use of a mixture of e(|ual cjuantities of naphthalene (finely 

 powdered) and boracic acid. This mixture was plentifully sprin- 

 kled in places frequented by cockroaches. The insects were greatly 

 reduced in numbers after the second application, which was made 

 after an interval of two weeks. 



The use of naphthalene for freeing a house from an infestation 

 of fleas was noted in the Agricultural News for May 9, 1914. In 

 this case a new house was seriously infested before being inhab- 

 ited. Nai)hthalene to a depth of 2 or 3 inches was put on the 

 floors of one or two rooms, and after twenty-four hours was swcjit 

 up and put into the other rooms and ])assages of tin- house, until 

 all were so treated The fleas were all killed out. 



Naphthalene is also very useful as a dry bath t'or dogs and cats 

 infested with fleas. The insecticide in a very tinely powdered con- 

 dition. f)r in the form of flakes, is rubbed into the coats of the dogs 

 or cats, and the fleas are r.npidly driven out by it. 'i'hev fall to 

 the ground in a stupefied condition; if the operation is carried on 

 over a sheet of cloth or strong paper, and thr naphth.iK'ne is freely 

 used, the fleas are killed by conlimied contact with it. and it c<in 

 be taken up and used over and over again. 



