This latter partnership continued about two years, when, on September 20, 1843, the firm of Lincoln & Herndon was formed, and it continued to the time of Lincoln's death.
When Lincoln began to practice law, it was the custom in Illinois to "ride the circuit," a proceeding of which the older communities of the East know nothing.

The State of Illinois, for instance, is divided into a number of districts, each composed of a number of counties, of which a single judge, appointed or elected as the case may be, for that purpose, makes the circuit, holding courts at each county seat.

Railroads being scarce, the earlier circuit judges made their trips from county to county on horseback or in a gig; and the prominent lawyers living within the limits of the circuit made the tour of the circuit with the judge.
It is said that when Lincoln first began to "ride the circuit" he was too poor to own a horse or vehicle, and was compelled to borrow from his friends.

But in due time he became the proprietor of a horse, which he fed and groomed himself, and to which he was very much attached.

On this animal he would set out from home, to be gone for weeks together, with no baggage but a pair of saddle-bags containing a change of linen, and an old cotton umbrella to shelter him from sun or rain.