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subsided at intervals of some weeks for a certain distance back from the face. Thus, a cavity for gas would be formed, which might extend for hundreds of yards following the line of faces. That this is so is frequently shown by abnormal quantities of gas coming off when a sudden weighting of a strong upper roof occurs, while at other times no gas can be detected. For weeks the gas filling this hidden space may remain comparatively pure ; but sooner or later some communications with the atmosphere of the mine will be affected, and will thus lead to the formation of a highly explosive mixture, mechanically, as well as by changes in pressure and by diffusion. A train may be thus prepared and lie ready in waiting throughout a network of crevices and fractures communicating with a distant place containing a body of gas which may have escaped detection. It is thus conceivable that if an explosion fires this train, the flame may be carried along until it reaches the distant gas, when it would set up a second full explosion, which would then run its course independently but almost simultaneously with the first."—That is not applicable to the present case at Ralph's Mine. 490. Can you suggest any reason why the gas should have suddenly exuded into this place ?— I. have an opinion that it was released by the fall. 491. But did not the gas cause the fall, or was the fall caused by some other means ?—1 have no evidence upon that point. 192. Do you say that the fall and the coming-away of portion of the material from the cavity caused the exudation of gas ?—lt possibly intersected a fissure which communicated with gas through a continuation of bedding planes or cracks in the superincumbent rocks above the coal, and perhaps in the coal-seam itself. Possibly the upper portion of the coal-seam contains a greater proportion of gas than the lower portion. 1 think that may safely be assumed. It is open, hydrous coal. The gas may have worked its way up to the impervious roof, and if you could take a sample of that coal and quickly subject it to analysis, and also a sample from the floor, the roof coal would contain more gas in proportion than the floor coal. I think that the gas which is produced in this mine comes from the upper coal. 493. Do you believe that it would be possible for that fall to have occurred, and the escape of gas, consequent upon the seismic disturbance at White Island, assuming that the eruption was at the same time ?—No, I do not think there is any connection between the two. • 494. But siesmic disturbances do liberate gas ?—lf there are fissures and cavities containing gas in the vicinity. 495. Are such cases not referred to in the text-book ?—I have never heard of them. 496. One author whom I have read on the subject says that earthquakes accompanied by earth motions may change the position of gas fissures in the earth's crust I —l have no knowledge of anything of the kind. 1 have no doubt that if in Rotorua there were magazines containing gas alongside volcanic or thermal activity gas would be. liberated, but as for saying that this explosion was due to the White Island eruption that is too far-fetched. 497. What is the distance ?—About two hundred miles, I should think. 498. I want to get at what is approximately the force of the explosion caused by an ignition of gas such as this. I understand that 1 cubic foot of gas is equal to 13 horse-power ?—I cannot determine that offhand. 499. Is it not your business to know that ?—Do you think I am an encyclopedia ? 500. Do you know how much flame 1 cubic foot of gas would generate ?—No, I do not know what flame a cubic foot of gas would generate ; it would depend upon the proportions of gas, also the temperature. 501. Firedamp \- Do you mean the length of the flame ? 502. The volume of flame. Take a cubic foot of firedamp of explosive mixture ; what would be the cubic contents of the flame ?—That is a matter of experiment, and I would not attempt to guess it here, especially upon the inadequate information you supply. 503. Do you think it would lead us to something if we knew ?- -You must start upon the percentage of methane which exploded, and state how much oxygen there is present, also if other gases are present. 504. Let us assume the average ?—This explosion was increased by the coaldust, which was a very important factor. You are asking a question which no man could answer offhand. 505. I suggest that the volume is as 1 to 21—that 1 cubic foot of gas will generate 2J cubic feet of flame ?—I do not deny that under certain conditions, but you stated no conditions. 506. Do you not think if that was so you could approximately calculate the quantity of gas if you knew the quantity of flame ?— But there is the coaldust to be taken into account. 507. Then you do not consider you could calculate it approximately ?—No, because the coaldust took control after the ignition. That is another impossible question you gave me to answer. 508. You stated yesterday that the explosives used in these mines did not conform to the standard adopted in England ?- I said nothing of the kind. What I said was, that the explosives used in these mines were not the permitted explosives on the English Home Office list. You are using dangerous explosives here, after you have been ordered by the Inspector of Mines not to use them. I mean at the Extended Mine. Ten days ago your company was ordered to use only such explosives as are on the Home Office permitted lists, and you are now breaking the law by using flame-producing explosives. That order covered both mines. The company is working the same seam under the same conditions in both mines, and there have been ignitions of gas in the Taupiri Extended as well as at Ralph's Mine. When the order was given by the Inspector that the company was to use only permitted explosives it covered both mines. 509. The Chairman.] But we are only into the explosion at Ralph's Mine ?—But the order for safety-lamps applied to both, as did that concerning permitted explosives. 510. Mr. Napier.] Do you not know that there is a barrier of coal between the two mines 2 chains in thickness ? —That is only 44 yards—not as far as from here to across the street.