Invention of the Crawler Tractor

Benjamin Holt designed the crawler tractor to work in the peat bogs of the San Joaquin Valley

| November 1999

  • The experimental Holt steam crawler, built about 1904. Note the 2
    The experimental Holt steam crawler, built about 1904. Note the 2" x 4" wooden track shoes and the massive roller chain drive.

  • The experimental Holt steam crawler, built about 1904. Note the 2

Exactly 95 years ago, on Thanksgiving Day, Nov. 24, 1904, three men stood on Aurora Street in Stockton, Calif., watching as Holt Junior Road Engine Number 77 passed. The engine was quite different from other steam traction engines of the day, even from other Holts. The familiar round drive wheels had been exchanged for a pair of tracks 9' long and 2' wide. Track shoes were wooden 2"x4" slats bolted to endless link chains, driven by sprockets. The machine's weight was supported by rollers that rode on top of the lower loop of chain. 

40 hp Number 77 was on its way back to the Holt factory after a highly successful field test in the spongy peat soil beside Mormon Slough, just outside Stockton. The machine had pulled four two-bottom plows two inches deeper than a Holt 60 hp wheeled steamer could. As Benjamin Holt and his friends (photographer Charles Clements, and painter John Shepard) watched the machine clank past, Clements, struck by the sight of the moving tracks, said "It crawls just like a caterpillar!" Ben Holt supposedly said "Caterpillar it is! That's the name for it!" A world-famous trademark, one still in use today, was born.

The tracks of Holt's first crawler had several names: "paddle wheels," "mud turtle wheels," "treadmill wheels," and "caterpillar wheels." Holt's nephew, C. Parker Holt, later recalled: "... the first 'Caterpillar' wallowed around so successfully in the soft mud of Mormon Slough that it was sent down to the Holt Ranch, where it operated steadily for an entire winter." The May 18, 1905 Farm Implement News reported that "In the Roberts Island tract, where a man could not walk without sinking to his knees, and where tule-shoed horses could not be used, the new traction engine was operated without a perceptible impression in the ground."

Benjamin Holt is generally credited with developing the crawler-type tractor still in wide use. Holt began building steam traction engines in 1890 with his first, "Betsy," 24' long and weighing 24,000 pounds. A single 10 1/4" x 12" cylinder developed 40 to 70 horsepower, depending on the steam pressure. The drive wheels were powered from a countershaft by means of massive link chains.

The fertile San Joaquin Valley runs northwest from Bakersfield between the eastern Sierra Nevadas and the Diablo and Temblor ranges on the west, to end just north of Stockton. Here the San Joaquin joins the mighty Sacramento, forming the Delta Region of the central valleys of California. The Delta country comprises 250 square miles of peat bogs, much of which is slightly below sea level.

Because of its vast potential for growing produce, the rich Delta islands were protected from flooding by dikes.

Galynn Ferris
4/26/2011 8:27:22 AM

There is a video of Holt Steam Powered Crawler No. 111 on YouTube. This was filmed at the Best of the West show in June 2010.


Farm Collector April 16Farm Collector is a monthly magazine focusing on antique tractors and all kinds of antique farm equipment. If it's old and from the farm, we're interested in it!

Save Even More Money with our SQUARE-DEAL Plan!

Pay now with a credit card and take advantage of our SQUARE-DEAL automatic renewal savings plan. You'll get 12 issues of Farm Collector for only $24.95 (USA only).

Or, Bill Me Later and send me one year of Farm Collector for just $29.95.

Facebook Pinterest YouTube


click me