James Porteous was a Scottish immigrant, born in Haddington, Scotland in 1848. His father, William Porteous, had been a wheelwright and blacksmith who built and repaired carriages, wagons and farm equipment. After learning his basic skills, James Porteous emigrated to the USA in 1873 and settled in Santa Barbara, California. In 1877, he eventually moved to Fresno, California and established a wagon shop, where he prospered, manufacturing buggies and heavy wagons.
Having worked with farmers, Porteous recognised the dependence of the Fresno 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.
By 1883 he had invented the Fresno Scraper, the basic design of which forms the basis of most modern earth moving scrapers, having the ability to not only scrape and move a quantity of soil, but also to discharge it at a controlled depth, thus quadrupling the volume which could be handled manually.
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. This design was so revolutionary and economical that it has influenced the design of modern bulldozer blades and earth-movers to this day.
Between 1884 and 1910 thousands of Fresno Scrapers were produced at the Fresno Agricultural Works which had been formed by Porteous, and used in agriculture and land levelling, as well as road and railroad grading and the general construction industry. They played a vital role in the construction of the Panama Canal and later served the US army in World War I.
It was one of the most important agricultural and civil engineering machines ever made. In 1991 the Fresno Scraper was designated as an International Historic Engineering Landmark by the American Society of Mechanical Engineers. It is featured prominently in the Fresno Metropolitan Museum.