See quotations.

1

1823.  They frequently make these jumpers to convey their game home.—J. F. Cooper, ‘The Pioneers,’ ii. x. (N.E.D.)

2

1833.  Did you ever see a jumper? Probably not; so I ’ll describe one to you. It is a primitive kind of sledge, or traineau. A couple of hickory poles are so bent as to serve for both shafts and runners; on these is placed a crate, supported by four props.—C. F. Hoffman, ‘A Winter in the Far West,’ i. 194 (Lond., 1835). (Italics in the original.)

3