surcingle

The saddle should be kept in its place by the elastic webbing girths, and not, as the common error is—probably from the facility of tightening it—by the hard, unyielding, leather surcingle.

From Hints on Horsemanship, to a Nephew and Niece or, Common Sense and Common Errors in Common Riding by Greenwood, George

When girthed tie the string surcingle over the saddle; besides holding the reins, it now prevents the flaps flying up.

From Hints on Horsemanship, to a Nephew and Niece or, Common Sense and Common Errors in Common Riding by Greenwood, George

When the horse has hopped for as long as you think necessary to tire him, buckle a common single strap roller or surcingle on his body tolerably tight.

From A New Illustrated Edition of J. S. Rarey's Art of Taming Horses With the Substance of the Lectures at the Round House, and Additional Chapters on Horsemanship and Hunting, for the Young and Timid by Rarey, J. S. (John Solomon)

Over the saddle—folded twice, if not three times—was a large, thick, and fine blanket, as good a one as the rider could afford, which was kept in its place by a broad surcingle.

From Captains of Industry or, Men of Business Who Did Something Besides Making Money by Parton, James

You breathe outdoor air only in high-fenced grass paddocks around which you are driven in surcingle rig by a Cockney groom imported with the pigskin saddles and British condition powders.

From Horses Nine Stories of Harness and Saddle by Ford, Sewell