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" The honey-dew was noticed by the 

 ancients, and is mentioned by Pliny by 

 the fanciful designation of the ' sweat of 

 the heavens,' and the ' saliva of the 

 stars,' though he questioned whether it 

 is a deposition from the air, purging it 

 from some contracted impurity. More 

 modern philosophers have been quite 

 as erroneous and discordant in their 



dew, ' almost as fast as it was deposit- 

 ed,' to collect it in considerable quan- 

 tities, and convert it into the choicest 

 sugar and sugar-candy.' 



" The bees, however, he found to- 

 tally disregarded the honey-dew which 

 came under his observation. With the 

 opinion of Mr. Curtis I do not agree, 

 any more than does the Abbe Boissier 



opinion relative to the disease's nature. I de Sauvages, who, in a memoir read 

 Some, with the most unmitigable aspe- j before the Society of Sciences at Mont- 

 rity, declare that it is the excrement of j pellier, gives an account of ' a shower 



aphides. Others as exclusively main- 

 tain that it is an atmospheric deposit. 



and a third party consider that it arises I at Paris. 



of honey-dew,' which he witnessed 

 under a lime tree in the king's garden 



from bleeding, consequent to the wounds 

 of insects. That there may be a gluti- 



■ The various successful applications 

 of liquids to plants, in order to prevent 



nous saccharine liquid found upon the ' the occurrence of the honey-dew and 



leaves of plants arising from the first and 

 third named causes is probable, or 

 rather certain ; but this is by no means 

 conclusive that there is not a similar 

 liquid extravasated upon the surface of 

 the leaves, owing to some unhealthy 

 action of their vessels. It is with this 

 description of honey-dew that we are 

 here concerned. The error into which 

 writers on this subject appear to have 

 fallen, consists in their having endea- 

 voured to assign the origin of every kind 

 of honey-dew to the same cause. Thus 

 the Rev. Gilbert White seems {Natu- 

 ralist's Calendar, 144) to have had a 

 fanciful and comprehensive mode of ac- 

 counting for the origin of honey-dew : 

 he tells us, June 4th, 1783, vast honey- 

 dews this week. The reason of this 

 seems to be, that in hot days the efflu- 

 via of flowers are drawn up by a brisk 

 evaporation, and then in the night fill 

 down with the dews with which they 

 are entangled. The objection urged to 

 this theory by Curtis {Trans. Linn. Soc. 

 vi. 82) is conclusive. If it fell from the 

 atmosphere, it would cover every thing 

 on which it fell indiscriminately ; where- 

 as we never find it, but on certain 

 living plants and trees; we find it also 

 on plants in stoves and green-houses 

 with covered glass. 



"Curtis had convinced himself that 

 the honey-dew was merely the excre- 



similar diseases, would seem to indi- 

 cate that a morbid state of the sap is 

 the chief cause of the honey-dew, for 

 otherwise it would be difficult to explain 

 the reason why the use of a solution of 

 common salt in water applied to the 

 soil in which a plant is growing, can 

 prevent a disease caused by insects. 

 But if we admit that the irregular action 

 of the sap is the cause of the disorder, 

 then we can understand that a portion 

 of salt introduced in the juices of the 

 plant would naturally have a tendency 

 to correct or vary any morbid tendency, 

 either correcting the too rapid secretion 

 of sap, stimulating it in promoting its 

 regular formation, or preserving its flu- 

 idity. And that by such a treatment 

 the hone3'-dew may be entirely pre- 

 vented, I have myself often witnessed 

 in my own garden, when experiment- 

 alizing with totally different objects. 

 Thus I have seen plants of various 

 kinds, which have been treated with 

 a weak solution of confimon salt and 

 water, totally escape the honey-dew, 

 where trees of the same kind growing 

 in the same plot of ground not so treat- 

 ed, have been materially injured by its 

 ravages. I think, howjever, that the 

 solution which has been sometimes em- 

 ployed for this purpose is much too 

 strong for watering plants. I Jiave al- 

 ways preferred a weak liquid, and I am 



ment of the aphides, and he supported , of opinion, that one ounce of salt (chlo- 

 his theory with his usual ability, al- j ride of sodium) to a gallon of water is 

 though he justly deemed it a little quite powerful enough for the intended 

 ' wonderful extraordinary' that any in- I purpose. I am in doubt as to the cor- 

 sect should secrete as excrementitious i redness of Knight's opinion, as to the 

 matter, sugar; he even thought it pos- ; mere water having any material influ- 

 sible, if the ants, wasps, and flies, could ence in the composition of such are- 

 be prevented from devouring the honey- | medy, since I have noticed that standard 



