A 25-year-old Scot named
James Porteous asked a ticket agent for passage to
America in 1873.
By 1880 he was an American
citizen who had been woven into Fresno Valley farm
life. Valley agriculture depended upon irrigation.
That meant canal digging.
Fresno farmers had been using something called a
buck scraper to move earth. It scraped up dirt and
pushed it along in front. It was hard to pull and
hard to unload.
Porteus' C-shaped scraper had a blade along the
bottom. It scooped dirt as it was pulled along.
That much was like the buck scraper, but this
machine rode on runners and could be tilted. An
operator walking behind it could change the angle.
When it was full, he tilted it back and let it
glide on the runners. He could dump dirt as he
passed over low spots and smooth out terrain. He
could vary the angle of attack to match the soil.
It was soon being used all over the world. It was
one of the most important agricultural and civil
engineering machines ever made.
clipped from: www.uh.edu 
