tervening rights have arisen within the legal acceptation of the term. Under these circumstances, complainants cannot be allowed to claim— infringement by this particular defendant in continuing the manufacture and sale which it entered upon while the [original patent] was the only public announcement of complainant's alleged monopoly. See Autopiano Co. v. American Player Action Co., (C. D., 1915, 243; 217 O. G., 1055; 222 Fed. Rep., 276; 138 C. C. A., 38.)

* * *

(5,6) A reissue of a design patent, the original of which was taken out at a time when the rules of the Patent Office limited the applicant to a diagrammatic description, is not open to suspicion because the claims cover the dominant features and are not limited to a verbal description of nothing more than the exact diagrammatic drawing shown in the specification of the original patent-in other words, because the claims have been broadened. The defendant's inkstand is undoubtedly within the claims of the reissue patent and contains all the dominant features of the Ashley design. It is not enough for defendant, while using this design as a basis, to superimpose ornamentation thereon, even though the ornamentation is sufficient to make defendant's inkstand readily distinguishable by the casual observer from complainants. The changes made by the defendant must have proceeded so far that it cannot fairly be said that Ashley's design is a substantial and easily discernible feature of the completed structure. Such is not, I think, the case here.

While, therefore, the reissue patent is valid and infringed, this suit cannot be maintained against this particular defendant, because of its intervening rights, and the bill must be dismissed, with costs.

[U. S. District Court-District of Colorado.]

CORONA CHEMICAL Co. v. LATIMER CHEMICAL CO.

Decided November 18, 1916.

241 O. G., 302; 240 Fed. Rep., 423.

1. PATENTS-INVENTION-IMPROVED ACID ARSENATE OF LEAD.

The Hall patent, No. 1,064,639, for an improved acid arsenate of lead, better adapted, by reason of its minute and flocculent particles, to use for mixing with water to spray as an insecticide, Held void for lack of invention as being an improvement in degree only over prior products. · 2. PATENTABILITY-INVENTION-SKILL OF CHEMIST.

"The patentee took a step forward. As he says, it was only an improvement, and that only in degree. It seems the step was simple, an experiment that would occur to any one familiar with the art, when we consider the vast number of combined drugs and chemicals applied to useful and beneficial purposes. To monopolize each under the protection of the 16644°-18

patent law would go far to thwart progress. The field of advancement not covered by the statute is larger than the one within its terms. It requires only common sense to know that the smaller the poisonous particles were the longer they would remain in suspension for use in the spray, and would more completely cover the infected surface. And this was only raising efficiency in degree without the accomplishment of any new function. A chemical laboratory is on the same footing under the statute as any other workshop. Every-day knowledge of the chemist and not inventive genius prompted the successful experiment. In this respect the same rule which applies to patented machines applies to patented arts and products."

IN EQUITY. Suit by the Corona Chemical Company against the Latimer Chemical Company. On motion to dismiss bill. Motion sustained.

Mr. A. J. O'Brien and Messrs. Dyrenforth, Lee, Chritton & Wiles for the plaintiff.

Mr. W. W. Boughton for the defendant.

LEWIS, Dis. J.:

This is a demurrer to a bill charging infringement of rights claimed to be secured to plaintiff as assignee of Clare H. Hall to whom Letters Patent were issued covering improvement in acid arsenate of lead. The Letters are attached to the bill, and I take it that, for present purposes, it is not necessary to closely determine what is claimed in and defined by them; i. e., whether, under the statute, it is an art, article of manufacture, or composition of matter. The specifications set out a chemical process by which, in part only, the discovery was made. It is said in them that several steps were taken in making the discovery and are all necessary in the production of the improved article, the first consisting in the mixing or union of well-known chemicals, the resultant product being stated, which is then mechanically subjected to four separate physical treatments before the composition reaches its final stage of commercial usefulness. That is, the chemical resultant is pressed, dried, broken into convenient pieces and then pulverized in a pulverizer of the disintegrator type. This gives bases for a contention that the patent covers a process within the meaning of the statute as an art, while on the other hand the claims call for an article of manufacture or combination of matter. But regardless of that, the specifications present, in the light of common knowledge, the facts on which the sufficiency of the demurrer is rested. They set forth:

My invention consists in a novel material which is chemically acid arsenate of lead (PbHASO.) having certain novel and valuable physical properties particularly suiting it for use as an insecticide.

Acid arsenate of lead, when used as an insecticide, is mixed with a relatively large quantity of water, usually one part of the acid arsenate to 400 parts of

water by weight, and the physical mixture thus formed is sprayed upon the plants to be treated. Since the acid arsenate of lead is practically insoluble, the resultant mass is simply a physical mixture, and it is of the utmost importance when using it that the acid arsenate of lead be of such physical consistency as to remain suspended in the liquid, without substantial settling, during the period which will be occupied by the spraying.

The acid arsenate of lead has heretofore been made by precipitating from one or another of the various combinations of salts which will produce it, and the resultant mass has been treated in a filter press to form a pulp. In most cases, this pulp is the commercial product, the pressure being such as to leave about 50 per cent. of water by weight to the mass. In some cases. this pulp has been dried and pulverized, the dry acid arsenate of lead being sold in the form of powder. In use, both products have been added to and stirred in the requisite amount of water.

It has been found that the drying and pulverizing of the pulp, in practically every case, greatly increases its settling tendency, and, for that reason. prior to my invention, the pulp has been in greatest demand. The pulp, however, has certain important disadvantages. In the first place, the expense of packing and shipping, as compared with packing and shipping the dry product, is considerable. In the second place, the pulp in the hands of the consumer or midleman frequently dries out into a cake which cannot be mixed with water and which is therefore useless. In the third place, there are very stringent Federal requirements as to the percentage of water permitted in the pulp, and from the manufacturing point of view it is an exceedingly difficult matter to maintain the percentage constant, so that one part of a given batch may have fifty-five per cent. water. while another has forty-five per cent., with the result that the manufacturer may unwittingly subject himself to criminal prosecution. In spite of these disadvantages, however, the superior suspension properties of the pulp have led to its being the most popular form of acid arsenate of lead. I have succeeded, however, in producing a dry arsenate of lead of the composition PbHASO, which remains in suspension in water as well as any of the pulps heretofore manufactured and far better than any of the dry material of similar chemical composition. The difference in this property is of course caused by a difference in physical constitution, and the material is obtained by employing several steps which coöperate to this end.

As a first step, it is desirable that the material be thrown down in the form of the most minute possible partícles, and this result can be produced by using extremely dilute solutions of the reacting salts; as, for instance, sodium acid arsenate, NA,HASO1, and lead nitrate, Pb(NO3)2, the nitrate of lead being formed in a solution of one part of nitrate of lead to 150 parts of water. and the sodium acid arsenate being introduced in a relatively strong solution, say one part to ten parts of water and at slow speed. The precipitate thus formed is so fine and flocculent as to make it a matter of some difficulty to press it to the dryness at which commercial pulps are regularly sold. This fine precipitate is pressed in the filter press to what is known as a thirty-five to thirty-seven per cent pulp, that is, a pulp in which the solid matter is by weight approximately sixty-five per cent. of the cake. The cake is ejected from the filter press, dried, and pulverized in a pulverizer of the disintegrator type, after it has been broken up into pieces of a convenient size-say pieces which will pass an inch mesh. The resultant material is a fine, exceedingly light powder. While the dry bulk of the material, uncompressed, has little relation with the important quality of the length of time it will remain suspended in water, it

may be stated as a fact, for purposes of identification, that the present product has, in fact, a rather high dry bulk, about one hundred cubic inches or more to the pound, and this is a considerably larger dry bulk than that of the other dried products now available. It will be understood, of course, that this dry material can be compressed somewhat in packing, and the foregoing figure has reference merely to its unpressed condition as it emerges from the pulverizer in marketable condition.

The most distinctive and important quality of the present material lies in its capacity for remaining suspended in water in which it far excels all other dry materials now available. Since there is no recognized standard for determining or measuring this quality, I have devised a test to which I have submitted the various forms of acid arsenate of lead available. which test is performed in the following manner: In this test fifteen grams of the arsenate of lead is pulped with water and diluted until the total volume is 250 cubic centimeters, the mixture being performed in a cylindrical glass graduate of this capacity and with a diameter of approximately one and one-half inches. As the temperature of the water has a decided influence on the settlement, a temperature of very close to 15° centigrade has been used. The density of warm water being much less than cold, the settlement is noticeably faster at temperatures above 15° centigrade, and noticeably slower at temperatures below 15° centigrade. The acid arsenate of lead of course begins to settle, and after a short time a distinct space of clear water can be seen above, the lower part of the graduate remaining full of the white opaque mixture. In making the test which I have devised, the location of the line of separation between the clear water and the mixture is observed at intervals, and I have learned that my product settles in the following manner: At the end of five minutes, the line of separation is at 210 cubic centimeter mark, at the end of 10 minutes, at 175 cubic centimeters at the end of one hour, 92 cubic centimeters, at the end of twenty-four hours, 68 cubic centimeters, this last figure representing practically final settlement. I have tested samples of the materials on the market in dry form (with the exception of one or two of which I was unable to obtain samples), and I have also tested the various commercial pulps by first drying and then pulverizing the same, and I have also made similar tests on the pulps in their commercial condition. The foregoing rate of settlement is as slow as that of any of the pulps, and it far exceeds that of any of the dry materials available. For practical purposes, manifestly the rate of settlement during the first ten minutes is the important point, and although the rates of settlement of the different materials in the main correspond, I have discovered some instances where materials settle relatively slowly during the first ten minutes and relatively fast thereafter. However, my material not only settles slower, but settles much slower during the first ten minutes than any of the dry products available. In fact. the slowest settlement which I discovered with a dry product was 165 at the end of five minutes, and 105 at the end of ten minutes, and the largest final settlement which I observed was forty-five at the end of twenty-four hours, as against sixty-eight for my product.

It is thus evident that my product, while chemically the same as other materials sold for the purpose, has radical differences in its physical form, which differences are readily distinguishable by the simple settling test above outlined. It is also a fact that this physical test is directed immediately at the single quality of greatest utility in practice.

The claims are as follows:

1. The herein-described dry, soft, white balky powder essentially acid arsenate of lead (PbHASO,) distinguished by the fact that when mixed with water in the percentage of fifteen grams to a total volume of 250 cubic centimeters, and allowed to settle the line of demarcation between the clear and clouded parts of the fluid is not below 175 cubic centimeters, at the end of five minutes, and not below 140 cubic centimeters at the end of ten minutes.

2. The herein-described dry, soft, white bulky powder essentially acid arsenate of lead (PbHASO4) distinguished by the fact that when mixed with water in the percentage of fifteen grams to a total volume of 250 cubic centimeters, the line of demarcation between the clear and clouded parts of the fluid is approximately at 210 cubic centimeters at the end of five minutes and approxirately at 175 cubic centimeters at the end of 10 minutes.

The evident and conceded purpose, in its use as an insecticide, is to deposit on and thoroughly cover the infected surface with the poisonous material by ejecting it in a spray; and to thoroughly accomplish that end it is desirable that the poisonous particles be minute. The whole claim of the patentee is that he made the particles minute and flocculent. It is admitted that "my product " is chemically the same as other materials sold for the purpose, but that it has "radical differences in its physical form," and that

it is desirable that the material be thrown down in the form of the most minute possible particles, and this result can be produced by using extremely dilute solutions of the reacting salts.

The precipitate thus formed is fine and flocculent. That difference is said to be demonstrated by the fact that it remains in suspension longer when in water than any other dry acid arsenate of lead then on the market, and as long as the same chemical in pulp form then sold on the market as an insecticide. The same claimed super-quality of suspensibility would undoubtedly be manifested if the powder was cast on the breeze, which is but proof of its relative fineness. So that the improvement which the patent purports to cover is greater fineress and flocculence of particles and not suspensibility attributable to the law of gravity.

Concededly, for present purposes, the patentee's process was new, and the resultant composition was new in commerce; but if only new in the same sense that ground coffee and comminuted glue were new when they were first introduced, it was not new within the sense of the statute as construed; nor in the latter sense would the way in which it is to be made necessarily be new. The patented compound is claimed to have been discovered by combining the solutions of two other chemical compounds, sodium acid arsenate and lead nitrate, both old, well known and widely used.