1848.] Account of an Artesian Well at TtUicorin. 16T 



Planaria lunata seems to be extensively distributed. I have observ- 

 ed it for several years past in various parts of the Oarnatic, both in- 

 land and on the coast. Dr. Jerdon has met with it in Malabar, and 

 Dr. ^Valker informed me it was found in Assam. 



YI. — Account of an attempt to form an Artesian Well at Tu- 

 tic or in. From Official Papers. 



Amongst the numerous benefits for which we are indebted to the 

 science of geology, the power of indicating the probable site of 

 springs of water is not the least important, and especially so with 

 reference to agriculture. The manner in which water is supplied 

 from the sea, through the medium of the atmosphere, to fertilize the 

 earth by rains, and to furnish a perpetual supply of water for the 

 maintenance of springs and rivers is generally known, but the cause 

 and origin of those subterranean springs, the locality of which it is 

 the province of geology to indicate, are more obscure. Excess of 

 water in large tracts of land can be permanently drained at small 

 expense by methods which entirely depend on a consideration of 

 the geological substrata; and the obtaining of a supply of water by 

 means of perforating the earth depends also upon the same fore- 

 knowledge. An instance of this want of knowledge occurred a 

 few years ago in England. A gentleman residuig in Sussex having 

 witnessed the successful attempts to procure water, by means of 

 Artesian boring, in London and its environs, was desirous of having 

 the same operation performed on his estate. After boring to a great 

 depth, and undergoing considerable expense, he was informed that 

 the project was hopeless : a result, of which any one conversant 

 with the different geological formation (the Wealden sand) of that 

 part of the country, could have informed him. 



The modern method of obtaining water by means of perforations 

 a few inches in diameter may, in time, supersede the more expensive 

 mode of sinking wells ; but the effort may prove fruitless, unless 

 the geological structure of the district has been thoroughly investi- 

 gated. A stratum of chalk of a green colour indicates water, and if 

 the chalk is found mixed with clay and of a dark colour, it is a still 

 stronger indication that the sheet of water, which it is intended to 

 meet, is near. Some of these subterranean waters have an enor- 



