On the ninth of June, 1868, reissued letters patent No. 2,979 were granted to the Rumford Chemical Works, a corporation of Rhode Island, for an 'improvement in pulverulent acid for use in the preparation of soda powders, farinaceous food, and for other purposes.' The original patent, No. 14,722, was granted to Eben Norton Horsford, April 22, 1865, for 14 years, for an 'improvement in preparing phosphoric acid as a substitute for other solid acids,' and was reissued to the Rumford Chemical Works, as No. 2,597, May 7, 1867, for an 'improvement in the manufacture of phosphoric acid and phosphates for the use in the preparation of food, and for other purposes.'
The specification of reissue No. 2,979 sets forth the mode of preparing the acid, which is a dry pulverulent acid, described as having the capacity of being intimately mixed with dry alkaline carbonates, or other sensitive chemical compounds, without decomposing them or entering into combination with them, except upon the addition of moisture or the application of artificial heat. It says:
'This requires that the phosphoric acid, or acid phosphates, be mixed with some neutral agent, as flour or starch, gypsum, etc., so that action of the acid shall be prevented while dry, and shall, when moisture or heat is applied, be prompt, thorough, and equally diffused. * * * It may, among other uses, be mixed with dry alkaline carbonates, carbonate of potassa, or carbonate of soda, and remain in this state without evolution of carbonic acid until moistened or heated, thus making it a substitute for cream tartar and tartaric acid in the preparation of yeast powder or baking powder. * * * It * * * is suited to be employed as the acid ingredient in the preparation of self-raising farinaceous food. In order to make an article possessing these qualities, and suited to this office, it is necessary that a powder should be made which can be not only evenly comminuted and diluted, but one which shall have so little affinity for the moisture of the atmosphere that it may be mixed with flour and bicarbonate of soda in the practical preparation of self-raising flour.'
The claims of reissue No. 2,979 are four in number, as follows:
'(1) I claim, as a new manufacture, the above-described pulverulent phosphoric acid. (2) I claim the manufacture of the above-described pulverulent phosphoric acid, so that it may be applied in the manner and for the purposes above described. (3) I claim the mixing, in the preparation of farinaceous food, with flour, of a powder or powders, such as described, consisting of ingredients of which phosphoric acid, or acid phosphates, and alkaline carbonates, are the active agents for the purpose of liberating carbonic acid, as described, when subjected to moisture or heat, or both. (4) The use of phosphoric acid or acid phosphates, when employed with alkaline carbonates, as a substitute for ferment or leaven in the preparation of farinaceous food.'
On the first of February, 1869, the following instrument in writing was executed and delivered by the Rumford Chemical Works to one Allen F. Morgan:
'To all people to whom these presents shall come, the Rumford Chemical Works, a corporation transacting business in East Providence, in the state of Rhode Island, sends greeting: Know ye that the said corporation, in consideration of the agreement, of even date herewith, entered into between it and Allen F. Morgan, of Memphis, in the county of Shelby and state of Tennessee, does hereby sell, assign, and transfer unto the said Allen F. Morgan the right to use, within the territory described in said agreement, Horsford's patent cream of tartar substitute, for the purpose of manufacturing within said territory self-raising cereal flours, with the right to use and sell the flours so manufactured; to have and hold and exercise such rights within the limits aforesaid, for and during the time, and under and subject to the conditions and limitations, named and specified in the agreement aforesaid, of even date herewith, to which reference is hereby made as a part hereof.'
On the same day Morgan executed and delivered to the Rumford Chemical Works the following instrument in writing:
