262 TRANSACTIONS OF THE 



about four and a half feet below the surface, the mean height of the jjoint 

 of discharge may be taken to be the present surface of the meadow; and 

 the mean lift, the distance which it may be found necessary to keep the 

 surface of the water, in the main drain, below the point to which the sur- 

 face of the land may subside when drained and cultivated. This will not 

 vary much from four feet, which may be safely assumed as the mean lift ; 

 it will probably be something less. 



The depth of water to be annually raised is assumed to be thirty-two 

 inches, which, upon 13,000 acres, will amount to 1,510,080,000 cubic feet. 

 This quantity may be raised four feet by a steam engine of fifty horse 

 power, in 318 days, of twelve hours each; but as the rain fall is irregular, 

 amounting sometimes to no more than one inch per month, and sometimes 

 reaching nearly twelve inches, it will be necessary to provide means for 

 raising at least two-thirds of this 'larger quantity ; or instead of using a 

 fifty horse engine, which it would be necessary to keep in operation a little 

 more than twelve hours during every working day in the year, it will be 

 proper to erect one of 120 horse power, which will accomplish the work 

 required in the whole year, if worked 132 days ; and could raise the eight 

 inches of water, which it may sometimes be necessary to dispose of in str 

 single month, in a little less than 11| days, of twelve hours each ; or if 

 worked continually, as it might be in cases of necessity, in about 5| days. 



The proportion of steam power, to the extent of country to be drained, 

 will, when the low lift is taken into account, be found sufiicient to afford 

 perfect security against danger, or inconvenience from accumulations of 

 water in any part of the tract, provided the channels for conducting it to 

 the draining wheels are made of proper dimensions and kept in proper 

 condition. 



The cost of a steam engine of this size, with boilers, engine house and 

 draining machinery complete, at the English computation of twenty shil- 

 lings sterling per acre, will be $65,000. But as the execution of such 

 works is not so well understood here as there, we may add for contingencies 

 $10,000, making the cost of the whole, when in operation $75,000, or 

 $5.77 per acre nearly. 



With respect to the number, dimensions and arrangement of the ditches 

 and larger drains and water courses, for collecting and conducting the 

 water to the machinery to be raised and discharged, a pretty wide range 

 has heretofore been indulged in by draining engineers, the proportions of 

 the surface taken up by them varying from ^^ to ^ part of the whole. 

 It is proper to remark, however, that the larger proportion was used when 

 wind-mills alone furnished the power for raising the water ; and as these 

 were irregular and uncertain in their action it was, necessary to provide 

 means for storing the large quantities, which sometimes accumulated, in 

 consequence of a lack of wind to set the mills in motion. With steam 

 power to perform the worl^ provision for storing any considerable quantity 

 of vfsCter became unnecessary, as the engine could be started whenever 

 there was work to be done. This substitution, of steam for wind, there- 



