Engines of Our Ingenuity

No. 353:
THE FRESNO SCRAPER

by John H. Lienhard

Click here for audio of Episode 353.

Today, we meet a forgotten inventor who shaped a new world. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

A 25-year-old Scot named James Porteous asked a ticket agent for passage to America in 1873. "Where do you want to go?" asked the agent. "I have no idea," replied Porteous. "This family here just bought a ticket to Santa Barbara," said the agent. "Why don't you travel with them?" So Porteous did.

That may be anecdote, but it does help us understand Porteous. By 1877 he was selling wagons in Fresno, California. 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 badly needed better earth-moving equipment for their sandy soil. Farmers experimented with horse-drawn earth-mover designs. The problem was harder to solve than it seemed.

Yet Porteous solved it. His series of patents reveal a subtle thread of real inventive genius. 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.

Porteous called it the "Fresno Scraper," and he formed the Fresno Agricultural Works to build it. It was soon being used all over the world. It was one of the most important agricultural and civil engineering machines ever made. Fresno Scrapers served the US army in WW-I. The two-horse model retailed for $28, yet today's bulldozer blades are its direct offspring. The gigantic scraper-carryall earth mover is its grandchild.

Finally, at the age of 47, Porteous raised eyebrows in Fresno by eloping with a long-standing lady friend named Jenny Ritchie. No matter. He raised children and piled up inventions until he died at the age of 74. In his maturity, Porteous drank in the new 20th century. He owned Fresno's first car. He took up photography. He told his six children about the airplane he'd once invented. What's behind that story, we never find out. His last house is now a Boy Scout Headquarters.

Finally, when he died, his family found that he'd left behind a book of poetry. I suppose that's no surprise from a man who'd taken such active delight in shaping America.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)


Ortiz, M., James Porteous: Fresno's Forgotten Inventor. Fresno -- Past and Present. Vol. 23, No. 4, Winter, 1981.

The Fresno Scraper is being designated by the American Society of Mechanical Engineers History and Heritage Committee as an International Landmark. It is featured prominently in the Fresno Metropolitan Museum.


The Engines of Our Ingenuity is Copyright © 1988-1997 by John H. Lienhard.

Previous Episode | Search Episodes | Index | Home | Next Episode