THE PLOW IN AMERICA 147 



would take a land polish over its entire surface. He also 

 invented a process for cold chilling the base of the landside 

 and the lower edge of the share, not knowing that that same 

 thing had been done by Ransome, in England. This improve- 

 ment lengthened the life of these wearing parts. Henry Burden, 

 two years later, constructed a well-shaped plow which was 

 widely popular on account of its light draft. In 1820, in the 

 first recorded dynamometer tests of plows made in New York, 

 his plow had a draft of 250 pounds for a ten-inch furrow to 

 325 pounds for Jethro Wood's, depth of furrow not stated. 



After buying shares and moldboards for his plows for a 

 number of years, Joel Nourse, of Shrewsbury, Mass., and his 

 partners, failed in the manufacture of plows built according to 

 Jefferson's principle. Nourse then cut and hammered from 

 a sheet of lead a moldboard which he believed would overcome 

 the greatest defect in the Jefferson plow i.e., failure to turn 

 the furrow over at all times. In 1842 he brought out the 

 Eagle No. 2 plow, which was popular form any years. The 

 moldboard was of greater length than on the majority of 

 American plows, and had more twist at the rear than the 

 English and Scotch plows. It also approached more closely 

 than either to straight lines in a longitudinal direction. With- 

 out planning for this result, he found that the extra twist of 

 the moldboard pulverized the soil admirably. 



Governor Holbrook of Vermont later assisted Nourse in 

 designing plows and devised a system by which, if the longitud- 

 inal lines were carefully laid down upon the pattern, the vertical 

 lines were sure to be right, no matter what size or shape of 

 moldboard was desired. By his method straight lines ran from 

 front to rear, and from the sole to the upper parts of mold- 

 board and share. None of the lines was parallel, nor yet 

 radiating from a common centre. A change in the angle 

 formed by any of the transverse lines changed the direction 

 of the vertical lines also. The surface of the moldboard was 

 such that different parts of the furrow slice moved at different 



