8o4 HARVARD LAW REVIEW case should be held to fall within the general principle of govern- mental prevention above set forth.^^ It may, however, be thought that the argument previously developed, as appHed to such acts as the issue of priority certifi- cates, must be limited to cases involving contracts entered into prior to the establishment of the priority system. One who, after that system had been put into operation and had become thor- oughly familiar to the commercial world, made an absolute con- tract to make and deliver commodities of a kind on which priority certificates were issued might be said to have deHberately taken the risk of this sort of interference. It may be doubted, however, if such was the real intention of the parties in the ordinary case. Business men no doubt fre- quently find it convenient to make sales in an informal manner without the drafting of elaborate contracts, and the absence of an explicit statement that the seller's obhgation was subject to gov- ernmental interference or priority certificates should not be held to make the contract an absolute guaranty of delivery. As Holmes, J., said in a recent case (8) in which the doctrine of im- possibiUty of performance was given a rather broad scope, "Busi- ness contracts should be construed with business sense, as they would naturally be construed by intelligent men of affairs."^" Ih a recent English case a contract to export aluminum made after war had begun and exports were restricted was treated as a contract to make reasonable efforts to obtain an export license.^^ It is true that to export without a license probably was illegal, which would not have been the case with regard to the giving priority to an order on which no priority certificate was issued. Nevertheless, if an agreement to export is not to be treated as a guaranty to obtain an export license,^^ it may fairly be argued that 29 Cf. The Kronprinzessin Cecilie, 244 U. S. 12 (191 7), in which the court held that a German ship was excused for failure to deliver a cargo of gold in England by the fact that, since war was imminent, there was grave danger that such a course would have resulted in the capture of the ship and in the detention of the German passengers. »<• Ibid., 24. " Anglo-Russian Merchant Traders v. John Batt & Co. [191 7] 2 K. B. 679. See also Allan Wilde Transport Co. v. Vacuum Oil Co., Sup. Ct. Unoff. Jan. 13, 1919. ^ Such a guaranty woiild not be illegal, although it might have some tendency to cause the use of improper means to obtain such a license. See English case cited in preceding note.
