140 A TREATISE ON THE CONNECTIOxN OF 



in water, coal-tar, * weight for weight, is to be preferred 

 to soot, for the destriiflion of inseds, or as an ai-ticle of 

 manure. But as the quantity of coal-tar that is now ca- 

 pable of being made in Britain would be insufficient for 

 the purposes of Agriculture, it has led to the discovery 

 of a cheap method of preparing other substances, which, 

 most probably, will be found equally, if not more effi- 

 cacious, as manures, and in the destruction of insefls. 



These preparations may be sown by hand on the 

 ground, and there is every reason to believe they will 

 succeed, not only in the destrucftion of the wire-worm, 

 so. injurious to the roots of grain, and to the fly which 

 preys upon the tender leaves of young turnips, and other 

 vegetables, in this country ; but likewise to the ants and 

 sugar-cane borer, in the West Indies, and the Hessian 

 fly in America. 



* Although the good cffeJls o( coal-tar, in repeated instances, have been mani- 

 fested, yet it is now cntirely'cat of use for vessels bottoms or sheathing, on account 

 of the protcHion it affords tliem from the attacks of the teredo or gribble worm, for 

 at least thrice the time which vegetable tar does. This has been the reason assigned 

 for its disuse by some of the most considerable and ctindid ship-builders and repairers 

 of ships in the River Thames, and other places in England. Vessels have been 

 known to perform six voyages to the West Indies with the same sheathing, when 

 payed' with coal-tar. 



DRAIN- 



