In addition to this retubing and recasing of the well hole, there were four, and only four, changes, none of which were process changes. There was, first, a new and heavier heater top in connection with the sulphur heating system; second, using a tapering plug at the end of the tubing, to facilitate dropping the tubing to place, using a shorter strainer and galvanizing it; third, making a tighter joint at the point in the tubing where the water flowed out and the sulphur ran in; fourth, using aluminum pump valves, to avoid corrosion. Having made these changes, the second trial was made by the same process as the first, but with the result that this time the tonnage was increased to 500 tons. Then, as it proved, the aluminum valves proved too frail; the pumping ceased, the sulphur congealed, and another delay ensued, until the spring of 1896. Hoffman testified as to this breakdown, its cause, and its remedy, as follows:

"After having put in the aluminum valves, the sucker rods, and made the connection of these rods to the walking beam, we started pumping. ** The second pumping we got about 500 tons of sulphur. The well up to this time had not what we call 'blowed'; by this I mean there was sufficient melted sulphur in the tubing to keep the steam and water out of this pipe, but finally we noticed that the sulphur stream had ceased flowing, although the engine continued to run freely. We then decided that our aluminum valves must have broken from the jar of the heavy column of sulphur above. In attempting to remove the barrel and the valves, we had to shut off the hot water to the well, and the melted sulphur again congealed around the 6-inch casing and tubing.”

Following this there was another cessation, or, as Hoffman testified: "The next sulphur we obtained was in the spring or early summer of 1896, and was from well No. 14, the original well drilled in while I was there."

In this interval changes were made, all of which were also not of process, but of apparatus to carry on the original process, as follows: First, the water supply from the adjoining marshes was supplemented by a river supply pumped into a ditch or canal 8 miles long; second, four steam boilers, of 150 horse power each, and 10 heaters, were added; third, to obviate congealing of sulphur when the tubing had to be pulled, rapid-acting, tubing-pulling devices and additional valves and appliances were provided, so that sulphur congealing would be obviated; fourth, instead of the frail aluminum pumping device, an air lift was provided. This air lift consisted simply of an inch air line, suspended in the 3-inch line. This latter line had been used in the former trials. It was thus described by Hoffman:

"The top of the 3-inch tubing was fitted with a T and our usual horizontal pipe was run out towards the sulphur bins. This pipe was provided with a safety valve as in our first operation. In the top of the 3-inch T was a heavy plug. This plug was threaded on both top and bottom sides, and in the bottom of the plug was screwed the 1-inch air line which hung down into the 3-inch tubing and extended to within probably 13 to 15 feet from the bottom of the well. In the top of this plug just described was also a 1-inch line which was connected with an air compressor, which had been sent us since our last dithculty in pumping by means of the sucker rod method, and which we hoped to use in raising sulphur in our next operation. We in all cases first

tested our lines as previously described. Steam was then turned into the 6inch casing. This was continued for probably 10 or 12 hours. We then turned one of the heaters into the 10-inch pipe and continued that for another 12 hours; of course, at all times keeping the heat going down the 6-inch casing.

On trying the well for melted sulphur after steaming probably 24 hours, we found the well sealed. We started our air compressor, and the pressure commenced to gradually rise, and in a short time the sulphur was flowing in gushes out of the sulphur discharge pipe into the bins. We continued pumping by this method as long as we could get any melted sulphur or had bin capacity for the same."

Hoffman testified the air compressor was known as the Clayton compressor; that it was a secondhand one; that while Mr. Frasch was at the well, and gave instructions to them how to use it, when sulphur was first pumped; that "we had tested out the air compressor after having placed it on its foundation."

A study of the proofs in this case also satisfies us that the long delays, before this sulphur process proved commercially profitable, were not due to unexpectedly meeting water in the sulphur deposit, or the necessity of further invention of apparatus to utilize Frasch's process, but were due to financial, fuel, drilling, and the like difficulties. Neither Hoffman nor Frasch assert that the presence of water in the sulphur strata was unexpected, or caused any change in their plans. When Hoffman began drilling under Frasch's directions, they had the drilling of the former wells; they knew these 13 wells were each and all flowing sulphur water. In that regard, Hoffman says:

"When I first went there, instead of 1 flowing well, there were at least-or to be exact, I think there were-13 flowing wells, and all of them flowed sulphur water freely. One of them we rigged up and used for bathing purposes. I do not recall the various sizes of the pipes leading from these wells, but each flowing well seemed to be flowing the full capacity of the outlet pipe from that well."

It is quite evident that Frasch recognized that the hot water he pumped into the wells probably passed off in these flowing wells, for as soon as Hoffman's first well, No. 14, was drilled, Frasch directed the 13 wells to be shut off. On that point Hoffman says:

"We had rigged up one well, as I before stated, for bathhouse purposes. After we had been steaming well No. 14 for some time, I noticed in bathing that the water we used in this bathhouse well was warmer than it had been. I took the temperature of the water, and found that it had increased. I advised Mr. Frasch, who was in Cleveland, of my observation, and he in turu advised me to shut off all the flowing wells, so as not to allow any of our hot water to possibly escape through that channel."

Indeed, we cannot read Hoffman's testimony, and escape the conviction that the water they encountered was nothing out of the ordinary, and they met it and neutralized its effects by increasing heat or damming off the incoming cold water. As to meeting the cold water by correspondingly increased heat at the surface, Hoffman's account is: "Q. Well No. 14, as I understand your testimony, was first steamed and pumped late in December, 1894? A. Yes, sir.

"Q. At that first steaming and pumping, what was the temperature of the water at the heaters? A. 330°.

"Q. You understood at that time that a considerable portion of this heat would be lost by the water while passing down the 6-inch tubing in the well, didn't you? A. We understood some would be lost by coming in contact with the cold water.

“Q. And it would be lost before the water ever reached the sulphur deposit? A. Yes, sir,

"Q. And that is one reason that you applied such a high temperature at the boilers or heaters? A. The matter of the proper temperature of the water that we were to put into the well was given us by Mr. Frasch. He stated that we would want to maintain a temperature of about 330 degrees to get our best results. I believe that about 95 pounds' steam pressure at the boilers gave us a temperature of 330 degrees at the heaters, and we had the safety valves on our boilers set that they would blow off at about 100 pounds' steam pressure, so that we would not increase the temperature of the water above the figure set by Mr. Frasch. He said at that time, if we used the water at a higher temperature, it would have a tendency to thicken the liquid sulphur."

In drilling the next well, No. 15, a fissure of 7 feet was discovered, and the incoming water was dammed back with sawdust. With reference to it, Hoffman testifies:

"In well No. 15, as I recall it, we struck some fissures after reaching the sulphur deposit, one fissure of which was at least 7 feet deep. Before turning the hot water into well No. 15, we pumped a considerable quantity of sawdust mixed with the water down the 6-inch casing, and allowed this to flow out with the cold water, in the hopes of bridging across some of the openings, so that our heat would not flow away when we started to pump the hot water. ' We probably pumped sawdust for 2 days before turning steam into the well?"

Frasch's account of the use of sawdust was:

"About that time we found that some wells gave out and ceased to pump when there had been no breaking of the pipes. I reached the conclusion that the cold sulphur water permeating the rock had broken into the melting zone, and brought the temperature of the melting water below the melting point of sulphur. I thought this might be remedied by pumping large amounts of a material like sawdust into the mine with the melting fluid, and that, if the quantities of sawdust were large enough, the channels through which the wild waters in the rock entered the melting zone could be sealed.

"One well, after pumping about 7,000 tons, at the rate of approximately 350 tons per day, ceased to produce. The pipes were all in good order, and we started to pump sawdust into the ground with the melting water. After pumping in about 6 carloads per day for 5 days, the well 'sealed' with the sulphur and promptly produced 39,000 tons more before the caving of the rock broke the pipes."

We are not overlooking the difficulties and delays met with in developing this process up to the complete commercial success it proved itself to be in 1903, but we are satisfied that such delay and difficulties were not caused by defects in Frasch's original conception or in means to utilize it. As already pointed out, Frasch was immersed in other work; he regarded this as a side issue; his visits were infrequent; the work was frequently suspended, for as much as a year at a time; the finances were such that the work was badly hampered, as Hoffman testified at length; and the appliances generally were on such a stupendous scale that changes or improvements required time. In that regard Frasch says:

"These improvements were made slowly, as all experiments had to be made on a ponderous scale, and the smallest change required a great deal of time. During the long intervals which necessarily elapsed between my visits to the mine, I could give this new enterprise no attention. It took months to drill a new well, when an old one was lost. At one time the work lay idle for a whole year before I could take it up again, and it was not until 1903 that we could see financial success ahead."

255 F.-62

We have thus described at length these earlier operations of Frasch, and the results attending them, with a view of testing the contention on which, in the final analysis, the plaintiff's case is based, or as summarized in the brief of counsel:

"This early conception of Frasch, as set forth in three of his patents long since expired, is relied upon by the defendant as its chief defense in this case; but those patents did not disclose any practical means of mining sulphur. They stated a problem, and not a solution of it. They suggested a line along which to invent, and, without further invention, their disclosures were useless."

We cannot agree with this contention, and in our judgment the facts do not warrant any such conclusion. We find no proof to warrant the conclusion now made, namely, that these expired patents of Frasch are based on the assumption that the sulphur deposit was free from water. Answering such contention, we may refer, amongst others, to these considerations: There is no such allegation or suggestion in the patents themselves; the bleed pipe T, shown in patent No. 461,430, for the reasons stated in discussing it at an earlier stage, is at variance with the contention now made; the 13 test wells, already drilled into the sulphur bed before Frasch began, told the character of that bed; the flow of sulphur water from these wells indicated sulphur contact; the Louisiana sulphur core, which Frasch said he had, of course, disclosed its own nature and formation, and there is no evidence that Frasch knew anything about the formation of Sicilian sulphur, and whether there was or was not water in the Sicilian mines; the testimony of Hoffman discloses no surprise at encountering water in the sulphur bed, and the account of Frasch makes no mention that the presence of water in the well he drilled (No. 14) caused him any surprise; on the contrary, the extract we have already quoted, and the sequence of events narrated by Frasch, tend to show that it was the water flow in the sulphur which led to the New York Company ceasing shafting operations, and that it was after that company ceased shafting that Frasch began drilling operations; when Frasch applied for the patents in suit, he made no contention or statement that he had discovered water in the sulphur deposit, and that its presence created difficulties which he had overcome by making further inventions.

We also think that a study of the application Frasch filed when he applied for patent No. 800,127, here in suit, clearly shows that his original process contemplated either a porous or nonporous sulphur rock, and that his alternative apparatus contemplated the use of one apparatus when the rock was porous and another when it was nonporous. Turning to the specification, we find Frasch thus describes the pioneer process and the apparatus for using it:

"Heretofore I have secured letters patent of the United States No. 461,429, dated October 20, 1891, for the recovery of sulphur by the process above indicated, and also letters patent No. 461,430 for apparatus for effecting such recovery. In said patents apparatus is described in which there are pipes by which hot water is circulated through the underground deposit, being introduced by one pipe and returned by another, and being always above the temperature at which sulphur melts. For raising the melted sulphur use is made in the patents of one of said pipes, or else an additional pipe is provided for the purpose. Either way the melted sulphur is forced up the proper pipe

by the pressure in the mine cavity or by the direct lift of a pump at the bottom of the sulphur pipe. For heating the water, fire-heated boilers are provided in said patents, through which the water to be heated is passed. With a sulphur deposit of such nature that the walls of the mine cavity are tight, and so able to allow the necessary pressure to be developed in the said cavity, the lifting of the melted sulphur by the hydraulic pressure can be effected; but in the case of a sulphur deposit in porous rock, which would not allow a sufficient pressure to exist therein, it was heretofore necessary to resort to a lifting pump, whose action was not dependent upon the tightness of the walls of the mine cavity."

His language and meaning are clear. The original process he was describing might be applied where the sulphur was tight, or as the specification says:

"With a sulphur deposit of such nature that the walls of the mine cavity are tight, and so able to allow the necessary pressure to be developed in the said cavity, the lifting of the melted sulphur by the hydraulic pressure."

On the other hand, if the hydraulic pressure could not be worked because the sulphur was porous, then another agency, to wit, a pump, was provided, or, as the specification says:

"But in this case of a sulphur deposit in porous rock, which would not allow a sufficient pressure to exist therein, it was therefore necessary to resort to a lifting pump, whose action was not dependent upon the tightness of the walls of the mine cavity."

In view of these statements of Frasch himself, made in 1897, when he was describing his original process, that the pump was for use in a porous formation, the contention now made, after his death, that his process was wholly for a tight deposit, does not carry conviction.

Laying aside such contention, and regarding the three patents in suit, in the light of a previous process which applied to both porous and nonporous sulphur, we address ourselves to the question whether they involve invention. Taking first the process patent, No. 799,642, which was applied for May 27, 1897, and granted September 19, 1905, whose claims 2, 3, 6, 12, 19, 21, and 22 are here in issue, we note that, of these claims, Nos. 3, 12, 21, and 22 alone were in the application as originally made, and none of them involve the element of porosity of structure, and that claims 2, 6, and 19, which do involve porosity, and the part of the specification, from line 30 on page 1 to line 9 on page 2, on which said claims are based, were only brought into the application in 1903. Turning to original claims 3, 21, and 22, we find they involve the use of air in raising the melted sulphur, and a top and bottom delivery of hot water to melt the sulphur. Both these agencies may be useful. They were, of course, novel in their application to sulphur mining in place, for sulphur mining was original with Frasch; but when Frasch had already disclosed the process of sulphur mining in place, and had actually melted and brought to the surface such sulphur by other means, we are of opinion it involved no invention to apply the hot water at two different levels, or after he had melted it to use air pressure as a means of bringing the liquefied sulphur to the surface. We therefore hold these claims as lacking invention, and therefore invalid. As to claims 2, 6, and 19, they involve porosity of the sulphur, and are based on the assumption that the process of this