The CHIEF JUSTICE

delivered the opinion of the court.

In regard to the first instruction given, it is not denied that the act of March, 1867, did exempt thimble-skeins and pipe-boxes. But it is claimed that the taxes paid were assessed upon them as eastings, and that the charge was calculated to mislead the jury.

Wo think otherwise. It is true that by the act of July 13th, 1866, a duty of three dollars a ton was imposed on castings of iron not otherwise provided for. By the same act, however, castings for iron bridges, malleable iron eastings, and certain other castings, were exempt. Under'this act, we have already decided that thimble-skeins and pipe-boxes of iron were subject *77 to duty; but by the act of March 2d, 1867, these articles were expressly exempted, and we think it would be too narrow a construction to say that the castings were liable, the articles themselves being exempt. This disposes'of the first exception.

•We think, as respects the second one, that there is no error in the charge prejudicial to the defendants. Taxes illegally assessed and paid may always be recovered back, if the collector understands from the payer that the taxes are regarded as illegal and that suit will be instituted to compel the refunding of them.

The third exception is to the instruction, that if the jury found for the plaintiff they might add interest. This was not contested upon the argument, and we think it clearly correct. The ground for the refusal to allow interest is the presumption that the government is always ready and willing to pay its ordinary debts. Where an illegal tax has been collected, the citizen who has paid it, and has been obliged to bring suit against the collector, is, we think, entitled to interest in the event of recovery, from the time of the illegal exaction.

Judgment affirmed.