After learning his basic skills, James Porteous emigrated to the United States in 1873, at the age of 25, and settled in Santa Barbara, California.
Having worked with farmers, Porteous recognised the dependence of the San Joaquin Valley on irrigation and the requirement for a more efficient means of constructing canals and ditches in the sandy soil, and he went about the task of devising an earth moving scraper for that purpose.
His ideas, combined with those of fellow-inventors William Deidrick, Frank Dusy, and Abijah McCall, all of Selma, California led to the Fresno scraper (1883).
Porteous purchased patents held by Deidrick and jointly by partners Dusy and McCall as he perfected his machine.
The blade scooped up the soil, instead of merely pushing it along, and ran along a C-shaped bowl which could be adjusted in order to alter the angle of the bucket to the ground, so that the dirt could be deposited in low spots.