David Josiah Brewer

“ What a patentee 'would have made if the infringer had not interfered with his rights' is a question of fact, and not 'a judgment of law.' The question is not what, speculatively, he may have lost, but what, actually, he did lose.'
It is true that that was an action for an infringement, and this for a breach of a contract; but still the rule of damages is the same. Actual damage is what the law gave in case of an infringement, (Birdsall v. Coolidge, 93 U.S. 64;) actual damage is all the law gives in case of a breach of contract. ”

“ Nor can it be assumed that profits, such as are claimed, were 'within the intent and mutual understanding of both parties.' It can hardly be presumed that the parties intended that the defendant should receive, as damages for breach of the contract, the profits of a sale which it could not make, rather than the profits of a sale that was made. There must, indeed, be some special circumstances before it can be inferred that parties intend that profits based upon a sale, which it is apparent could not have been made, should be the measure of damages. ”

“ The defendant never changed burners; never paid the three dollars; and there was no testimony showing the value of the lamp with the solid burner, or how much less it was worth than one with a tube burner. It does not appear that the defendant ever sold a lamp for less price on account of the solid burner. In addition to all this, a letter from the Pennsylvania corporation (while not entirely clear in its language) seems to carry the idea that, as soon as its bill for the 250 lamps is paid, it will exchange burners free of cost. ”