68 FEDERAL BBFOBTEB. �rubbed into the pores of the wood, "a hard, impenetrable substance, whioh in itself forms a protection to the wood." �TKe defendants made and sold, prier to the date of the bill and after the assignaient of the patent, wood Aller which is Bubstantially the plaintiff's article, and, like the plaintifif's, made from powdered quartz. It is not denied that the manu- facture and sale of this material is an infringement of the plaintifs patent. Goodyear v. N. J. G. R. Co. 1 Fisher, 626. �Tbe principal defence is that the defendants bad the right to use the material under a lieense from James Perry, to •wbom was granted a patent, dated September 11, 1866, wbioh it is claimed inçludes the Wheeler patent. The speci- fication and claims of the Perry patent are as foUows: "This invention consista in the use of a certain clay or mari, known to chemists as 'silicious mari' or 'infusorial eartb,' in the process of filling the grain of wood to' be polished. The operation is effected in a similar manner to that in whicb otber materials for the same purpose are used ; that is, by rubbing the substance well into the pores and grain of wood in order to produce a close, bard surface, capable of being bighly finisbed; rotten stone and plaster of Paris being the most common materials used in this process. �"Infusorial eartb, sucb as my invention embraces, may be used in the same state in which it is taken from the eartb, viz., an impalpable dust or powder of silicious character, or it may be prepared for use in a manner which I will now describe. One-half ounce of sal ammoniac, (muriate of ammonia,) one- balf pound of white vitriol, (sulphate of zinc,) one ounce of gum arable, and half a gill of gum tragacanth, (dissolved in water,) are put into two quarts of water, and stirred until the wbole is dissolved. Six pounds of silicious mari are tben well stirred up in the solution, and, if it is proposed to give the material any shade of color or dye, the requisite coloring mat- ter can be put in at tbis point; the wbole mass being well mixed up together. A pint and a balf of linseed oil is also tiioroughly stirred up in it. A cbemical affinity is produced by the mixture of these ingredients, the bases and salts con- tained uniting the oil, water, and mari, and the preparation ����
