-2fto 



THE AGEICULTl-RAL NEWS. 



August 29, 1914. 



INSECT NOTES. 



PARANAPH AND SCALO. 



Petroleum nils useil in Viuious ways have tnr a number 



■of years past been considered useful insecticides, and there 



have appeared from time to time ditt'erent formulae calculated 



to provide a mixture of tliese oils with water as sprays and 



"washes. 



The ordinary kerosene emulsion consists of kerosene, 

 jjarafRu or illuminating oil, as it is called in ditt'erent places, 

 mixed with a hot solution of soap and water, the intimate 

 mixture or emulsion being brought ;iViout by violent agitation 

 or cliurning. 



Mr. H. H. Cousins, M.A., in his book T/ie Chemislri/ of 

 the Gulden (London, 1.^99) mentions the value of parathn 

 (kerosene) emulsion as an insecticide, and gives directions for 

 preparing it. Following this, itr. ('ousins makes the following 

 -statements under the heading Paraffin Naphthalene emulsion: 

 -' Tlie idea occurred to the writer that a substance which was 

 -soluble in both .soap and paraffin might greatly assist in the 

 production of a paraffin euiulsion of a kind and perfection 

 su|)erior to that olitainable with paraffin and soap alone. 



'As the result of exhaustive experiments naphthalene 

 pro\ed to have tlie desired properties, and it was found that 

 H .saturated solution of naphthalene in paraffin oil combined 

 with Ijoiling soft soap with great ease. A semi-solid product 

 can thus lie easily prejiared, which readily <lissolves in water, 

 and at a strength of 1 to U parts to KKI parts of water has 

 ])roved a most effectual and sound remedy for sucking insects. 

 'If properly made this compound will keep indefinitely, 

 and when dissolved in water gives an emulsion of such 

 Knencss that no visilile separation of oil takes place even after 

 standing for weeks in the open air. 



'The materials are cheap, and for home use this remedy 

 can lie prepared at a co.st of 1-. t(p l.«. -2d. ]m- 100 gallon.s of 

 tlie wash as used. 



'In using this, as with all washes for sucking insects, the 

 .one essential for success lies in the production of a liquid 

 ,<-apable of lathering freely, and of thoroughly wetting the 

 foliage and the adherent insects. 



'The proportion of .soap shouUl Ije such as to secure a good 

 lather, and on this account the proportion of jiaraffin in the 

 .solid product .should not exceed 20 per cent.' 



In a circular issued by the Jamaica Department of Agri- 

 culture, by Mr. Cousins (the Director) an account of the u.se 

 -of the paraffin naphthalene emulsion is given with special 

 reference to its suitability as a spray wash for the killing of 

 •cattle ticks. In this circular it is stated that this substance 

 was invented and patented in England liy the writer in l.^Oo 

 ■ under the name Paranajih, and tlie follf)wing formula for its 

 preparation is given; 'To 56 It), of the best soft soap (the 

 Chiswick Imperial is recommended) add i gallons of water. 

 -8imnier over a fire with constant stirring until all lumps have 

 disappeared, and a perfectly uniform melt has been obtained. 

 .Vdd 6 It), naphthalene. Stir until dissolved. Ilemove 

 from the tire and add l' Imperial gallons of ordinary kerosene 

 oil. Stir until uniform. The finished product is semi-solid and 

 dissolves readily in cold water so as to give a milky emulsion.' 

 This amount of material makes about 80 R). of Parana))!) 

 containing about 17 Bo. of kerosene or atiout 29 per cent. 

 The patent on this substance has since lapsed and any one is 

 free to make and use the emulsion. 



In the West Indian Bulletin, Vol III, p. ."^19, published 

 in March 1903, an article a]jpeaied liy Mr. H. M. Lefroy, M.A., 

 entitled Crude Oil and Soap, a new general insecticide. In 

 this article Mr. Lefroy describes his experiments in the prepa- 

 ration of an cninlsion of the crude petroleum, at that time 



being produced in Bartjados, with whale oil soap in the 

 attempt to prepare a mixture comparable with the heavy oil 

 sprays at that time coming into very general use in the 

 United States. 



Ill this account it is stated that the idea of u.siiig 

 naphthalene to aid in bringing aViout a combination between 

 oil and soap originated with Mr. Cousin.s. The sugges- 

 tion to use naptlialene for the purpose mentioned is an 

 important one which has had the effect of producing a more 

 effective series of insecticides. For this suggestion 

 Mr. Cousins deserves con.sideral ile credit. Mr. Lefroy exjjeii- 

 mented with the Barbados crude oil and fc)und that 

 a very satisfactory emulsion could be obtained liy the use of 

 10 11). wliale oil soap heated to the boiling point, or. if it 

 contained much water, boiled for a time to drive otf the 

 excess. In the boiling soap, 4 ounces of naphthalene wei-e 

 dissolved; the 5i pints of crude Barbados oil were added and 

 the mixture accomplished by vigorous stirring. This pro- 

 duced a semi-solid substance containing some .30 per cent, of 

 crude oil and 60 per cent, of whale oil soap. 



This mixture proved to lie a very useful insecticid", 

 easily <lissolveil in water and efficient in killing scale insects 

 on plants. 



The production of Barbados oil has cea.sed, however, and 

 as a result this mixture is no longer olitainalile. 



More recently Mr. .J. C. Moore. Agrii'ultural Superin- 

 tendent. St. Lucia, carried out experiments in making a modi- 

 cation of Paranaph and Lefroy's mixture and produced 

 a substance to which he gave the name Scalo. This differs 

 from Paranaph in that it contains a much greater amount of 

 kerosene, about 50 per cent. It was expected that this 

 increase of kerosene would increase the efficiency of the spray 

 mixture and while no comparative tests between the two 

 emulsions ajipear to have been carried out, it has been founci. 

 that Scalo is very efficient in treating the more coninion scat-; 

 in.sects. Scalo is made as follows: — 



Whale oil soap 56 tti. 



Water (2 gallons) 20 „ 



Naphthalene (crude) 6 ,, 



Kerosene, one case of 8 \ 

 Imperial gallons I 65 ,, 



making 147 lb. containing aliout 50 per cent of kerosene. 

 The whale oil (or li.sh oil) soap lieing of itself an insecticide 

 of considerable value tends to increase the value of the ini_\- 

 ture over that prepared liy the use of soft soap. 



The whale oil soap and water are heated until the soap 

 is dissolved aJi<l the naphthalene is added. This mixture. 

 while boiling vigorously is taken away from the fire and 

 half the kerosene oil added and stirred in with a flat paddle. 

 By the time the oil is well stirred in. the mixture will be 

 cool and it will be necessary to heat it again to the boiling 

 point in order to work in the remainder of the oil. Care, 

 must be exercised in this part of the process that there i.- 

 iiot a sufficient amount of free oil present to take lire. 



It will be seen that this mixture. Scalo, possesses -ome of 

 the points of both Paranaph and Lefroy's mixture u>ing the- 

 essential principal of one I'ii. the combining pro)).-itie- of 

 the naphthalene and the whale oils (or fish oil) soap. v*liich 

 in itself is an efficient insecticide, to take the plmr of the 

 ordinary soft soap. 



Kero.sene emulsion, Paranaph, Lefroy's mixture and 

 Scalo are used for the same purposes. They are emulsions of 

 mineral oils and soaps suitalile for use against a gn-at variety 

 of sucking insects on plants, ticks oil cattle and dogs, and 

 they may even tie u.sed against biting in.sects if these live 

 exposed and are sufficiently soft-liodied to tie s,)si->'|)lil,le tn 

 a contact poison. 



