This appeal from a decree dismissing the bill turns on the narrow question of whether patent No. 1,281,690,- granted October 15, 1918, to Stem, for a method of stopping leaks in automobile radiators and other receptacles, involves invention. If it does, the defendant is an imitation infringer.
Turning first to the disclosure of the patent, the specification states it is a method of stopping leaks in metal vessels, which “involves the employment of a leak-stopping ingredient which, with water, is adapted to form a colloidal solution.” We pause here to say that a colloidal solution is one which does not settle in fluid, but remains in suspension. The patentee goes on to state:
“The essential constituent of the composition is a substance commercially known as cube gambier, which is an extract from certain trees or shrubs and contains eateehin and tannin, although other hark extracts containing eateehin or similar compounds may be employed or substances having similar characteristics. The composition may be produced in the following manner: the gambier may be liquified by heat, and while hot may be added to a mixture of seven parts by weight of alcohol and one part by weight of water. This mixture may be plaecd in a closed vessel and agitated and heated for say 24 hours, and the temperature may bo gradually increased until the contents reach about 350 degrees F., at which time a considerable pressure will be developed, then tho temperature is reduced to about 35 degrees F., whereupon a colloidal solution is formed, which may he placed in cans for shipment; the gambier, which is the leak-stopping ingredient, being in a colloidal state.”
Cans containing about a half pint of this solution are sold by plaintiff and defendant at $6 each, and small quantities thereof are poured in automobile radiators. When a leak occurs, the solution finds the leak and escapes through it, or, as stated in the specification:
“The colloidal solution of water and leak-stopping ingredients thus contained in the vessel will be circulated by any suitable means, such, for instance, as a pump associated therewith, so that the leak-stopping ingredients will he positively moved about and find lodgment at the leak opening, and when so disposed will in time be exposed to tho air and become hard, and practically insoluble, and thus effectively close the opening.”
That this solution was useful is proved by tho public buying from both plaintiff and defendant at high price for small quantities. Tho proofs show it was used by the United States on all long-distance aeroplane flights since the NC-4 trans-Atlantic flight in 1919, including the McMillan Arctic expedition of 1925. We shall not quote the evidence bearing thereon, but restrict ourselves to saying that the results in metal leak stopping by this fluid solution present a case of an unusual kind, and we are satisfied the contribution of this patentee to the art was one so effective, unlooked for, and simple as to brand it unusual in character. Moreover, the disclosure was original and novel. Gambier had been used for years in the tanning art and in other ways; its qualities were known. Indeed, in conneetion with pulverized asbestos, a Chilean tree, glucose, and claret wine,, gambier was made part of a mixture in patent No. 1,117,526, to Seely, for “coating the interior of inflatable tires to render them puncture proof,” an altogether different conception, employed for a different purpose- and with different result. But no one before-Stem conceived tho idea of using gambier in-suspension in water, where the solution *554would remain fluid until a leak occurred. 'When this happened, for it was not a preventer of leaks, as was Seely’s preparation, then the solution, in escaping, brought the suspended gambier into contact with the air, with the result that it hardened, automatically became a solid plug, and its hardness •was so intensified by the action of the air that it was practically as impervious to perforation as the surrounding metal.
The prior art had used solids carried in fluids for plugs, and was based on the continuance of solids as solids at every stage. These solids plugged the holes, but unfortunately they also plugged the channels leading to them. In Stem’s case what was eventually to become a solid was kept a liquid initially, and until functionally needed, and 'then, and then only, automatically became solid at a time and in a position where it . blocked the path of its own escape by automatically soldering, so to speak, the leak. The use of gambier for such purpose, its continuing in suspension in water, its faculty of not clogging the channel, its solidifying when escaping through- the leak, all matters elemental in this method and use of colloidal state, made a combination so unusual, unex- ■ peeted, novel, and useful as to place it in the - zone of invention. The disclosure was awarded claims which we shall not discuss in detail, and, referring to claim 1 only, which is quoted in the margin,1 we are of opinion it covers the situation and-method disclosed in the patent, and protects the colloidal gambier, the only leak-stopping element in that state here in issue, disclosed by the patentee and used by the defendant. The scope of the. claims in the case of other elements is not before us, and therefore not decided.
The decree below is reversed, with direction to enter a decree sustaining the validity of the patent and ordering an accounting for infringement.
The method of stopping leaks in metal vessels containing water, which consists in placing a composition comprising a leak-stopping ingredient in a colloidal state contained in the water in the vessel, and forming with said wafer a colloidal solution, and circulating said solution to move the leak-stopping particles and cause them to enter a leak opening, whereupon they harden upon the exposure to air.