Here is a vintage magazine advertisement for a two-wheel velocipede. The ad states that this early bicycle was sized for boys with a 26-inch wheel and it had a plain seat. The cost was $25 or $30 with horse. I don’t know the meaning of “with horse”. The ad also states that “Any Boy can learn himself to ride in a few hours”.

Here is a black and white clip art illustration of the bike from the ad.

The ad is from the March 1869 issue of Harper’s New Monthly magazine.
Click on images to enlarge.