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CRANE FOE RAISING MARL BY HORSE POWER. 



runs on iron pins let into thimbles. The lever is in two pieces, 

 one fastened in the cylinder with a groove at the end, into which 

 the other is let, and secured by a sliding iron clamp. When the 

 marl is discharged from the box, and the swoop swung round over 

 the pit, in nautical phrase, by unshipping the end of the lever, the 

 rope unwinds, and the box descends without moving the horse. 

 The circle in which the horse travels ought to be twenty-one feet in 

 diameter. The second and third posts are supported by side braces. 



" The cost of the machine is small, though I cannot make an 

 exact estimate. The carpenter who did the work was hired by the 

 day on the farm, and was taken off with other jobs ; but his bill 

 could not exceed eight dollars. The cost of the iron-work was 

 ten, and one hundred and sixty-five feet of inch rope, at eighteen 

 and a half cents a pound. The timber, taken from my own woods, 

 may be estimated at five dollars. The rope I find soon wears out, 

 and I intend to supply its place with a light iron chain. 



" When the marl is uncovered, with one efficient hand in the pit 

 and a less efficient one to discharge the boxes and drive the horse, 

 five hundred bushels may be raised in a day. The work is not 

 oppressive to the labourers. The teams stand on high, dry ground; 

 no sloughs to plunge through, and no hill to climb. The swoop 

 is turned by a small rope over the carts, and the marl immediately 

 discharged into them. I work four carts, with two sets of oxen to 

 each. They came out of the winter lean and weak ; and now, with 

 green clover for their food, at the distance of a half to three-quarters 

 of a mile I draw out from four to five hundred bushels a day, and 

 my oxen have improved. My work goes on with ease and expedi- 

 tion, without stoppage to mend roads, or to clean ditches." 



The machine which will be described below is used at Fortress 

 Monroe for raising sand from the fosse to fill the ramparts; and 

 has been found by experience to be the best contrivance of all 

 which have been tried for that operation, and for which an immense 

 amount of labour was necessary in constructing the defences of the 

 fortress. Precisely the same manner of operation is required for 

 raising marl from deep pits, and there can be no doubt of this 

 being a more effective machine for that purpose than any worked 

 by hand. The force applied is the weight of the labourers; on 



