Plaintiff was employed by defendants to make certain alterations on a steam-engine, defendants agreeing, in the event that a certain result was attained by such alterations, they would pay the plaintiff one thousand dollars; plaintiff to forfeit all compensation for labor or materials if the alterations did not produce the desired result.

The nature and extent of the alterations were left entirely to the option of plaintiff.

In the progress of the work, plaintiff attempted to remove a certain copper pipe belonging to the engine, for the purpose of making alterations in it, but was prevented by defendant; plaintiff then abandoned the work.

Plaintiff had judgment below for the full amount named in the contract, and defendants appealed.

In Baldwin v. Bennett, 4 Cal., 392, it was held that where, from the nature of the contract, it is not practicable to ascertain the amount of damages sustained by a breach of contract, the measure is the price agreed to be paid.

*365In this caso, it is impossible to arrive at the precise amount of damage sustained by plaintiff; if the nature, extent, and probable cost of the alterations contemplated by him were known, then the measure would be the difference between such cost and price agreed to be paid. But as there was no evidence on this point, the rule adopted by the Court below was the only one applicable to the contract.

Judgment affirmed.