Imatges de pàgina

that no increased risk was caused by produce combustion, considering the the introduction of that process. state of the premises. The use of the Damages, 72001.

oil, as described, for two months would produce no change in it, with respect

to the facility of producing gas. When COURT OF COMMON PLEAS, oil is heated to a temperature of 640

degrees, it is changed to an inflamDecember 13.

mable nature. At 500 it produces a

light aqueous vapour, which, carrying Severn, KING, & Co. v. The Phe- some oil with it, might burn, but, at NIX INSURANCE COMPANY. that temperature, it could not ascend

above an inch or two, if it ascended This prosecution related to the at all. It is impossible that at 360 same fire, and stood on exactly the degrees any vapour could pass at the same grounds as the preceding. In mouth of the leaden tube, which is 16 the course, however, of a trial, which feet from the vessel. No inflammable lasted five days, much additional evi- vapour, even at the heat of 600, could dence was produced, among which pass from the oil vessel through the is the following:

tube. It would become oil, and fall Dr Thomas Thomson.--I am Pro- down again before it reached near that fessor of Chemistry in the University height. He spoke of whale-oil, and of Glasgow. I have directed my at- the oil of cod. He tried them both. tention to the apparatus before me: He tried the action of heat at 360, this was about the beginning of last for six weeks, on oil, and the only June. I am acquainted with the or. change was, that the colour was darkdinary mode of refining sugar. In my er, and, when cold, it was thicker ; but opinion, the present plan would be at. it was not rendered more inflammable. tended with much less danger. The Oil, at a temperature of 640, below temperature here was about 360 : oil which it will not produce gas, emits a boils at 640. There would be no dan- smell the most offensive in existence. ger if the machine which contained I have been knocked down by it. I the oil were to leak ; if it were a great know what is called dipples-oil

. An leak, it would put the fire out; if a application of heat at 360, for two small one, it would burn like coals. months, would certainly not produce There was nothing emitted by oil at dipple-oil. I have passed whale-oil the temperature of 360 but a little through a red-hot iron tube three water, which is not the least danger. times successively, without producing ous. I have tried experiments on dipples-oil. Dipples-oil is very inflamwhale.oil, and I have not been able to mable, and boils at 180 degrees. I satisfy myself that it emits gas at so failed to produce dipples-oil with my low a temperature as 640; certainly own apparatus. It is impossible for not lower. It would require a very such a vessel as was used by Severn intense fire to produce that degree of and Co. to produce dipples-oil. No heat. The gas produced from oil will change could take place in the oil at not burn unless it be mixed with six the heat of 350 deg. for two months, times the quantity of atmospheric air, except its becoming blacker and thick and not with more than twelve times the er. At 440 deg. it would not produce quantity. If the whole of the oil used any change such as he before mentionat Severn and Co.'s were to be turned ed. There is a substance which is found into gas, it would be impossible to in whale-oil, which, by great pains and VOL. XIII. PART II.


care, may be separated from it, and introduced into the vessel, was exa this, at a red heat, would produce a tinguished. The vessel was as large as gas; but this would not burn. I think the original one. There were about it is impossible that any danger could three inches of oil in it. The other occur in this vessel if there were a fire answers of this gentleman concurred, twenty miles long under it. It never as far as his personal knowledge of the could be heated beyond 640 deg. in an facts extended, with the answers given open vessel. If the vessel were shut, it by Dr Thomson. might be heated more, but it would Cross-examined by Mr SCARLETT.burst. In the oil vessel used by Severn His knowledge as to oil, in this case, and Co. it was impossible the oil could was confined to what he saw on Sa. have gone into the pipe and got out. turday last. He had not made any ex. At 450 deg. oil increases about a fifth periments himself, as to oil. He had of its bulk; but as there were two. for some time given great attention to thirds of the room vacant in this ves- chemical subjects in general. sel, it was impossible the oil could have William Thos. Brande.- Is Profes. been raised into the pipe. At the tem- sor of Chemistry, and Lecturer to the perature of 340 oil gives out an aque- Royal Society: He made several exous matter-a steam which condenses periments, with respect to this case, at the top of the vessel. From thence before and sinee he was first examined. it falls back into the oil; and as the He got a copper basin of sugar and water is heavier than the oil, it sinks; one of oil, and placed them on a fire, in its way down it is expanded again When the heat of the sugar was 400 by the heat, and makes a crackling degrees, he put a lighted paper to it, noise as if the oil were boiling. There and it took fire ; but the paper was is, however, no danger in this. If it quenched when put into the oil. He were put to me as a problem, I do not had made the experiment with the bethink I could set the place on fire by lief that the oil would take fire first. this, unless the machinery was altered. This was before he was last examined. Sugar is very inflammable. It will The oil was 600 deg. when the therburn when it boils over. It would mometer was taken out. He then put then burn as it ran on the floor. I a lighted taper to it, and a blue lamlook

upon sugar as the most combus- bent flame played for a while on the tible substance next to gunpowder. top, and went out. This was in the Pure sugar boils at 250 deg. At a few daytime. What appeared to him to degrees higher--I believe not more burn was an inflammable vapour. He than ten—it begins to emit an inflam. did not consider that the same effect mable gas, like that from oil, but the would be produced by putting the ta. difference is, they are produced at dif. per to a pipe at the bottom of the ferent temperatures. The fame of vessel. He tried experiments on new bugar, if the place were close, would and old oil. He took some oil which be red ; if in the open air, it would for 29 days had been exposed to heat probably be white.

of from 400 to 500 degrees ; and ba. Dr Davy, a member of the Royal So- ving again heated it in a bolt-bead, or ciety, and a brother of Sir Humphrey bottle with a long neck, he applied a Davy.-Heard Dr Thomson exami- lighted taper to the tube from it, but ned: never made any experiments him- found no vapour or gas. He observed self on this oil, but saw some made, on that an aqueous vapour was formed, Saturday, at Messrs Severn's. At a which condensed in the neck of the heat of 350 or 360, a lighted paper, bottle, and, falling down into the oil, occasioned a crackling noise, as if the perature of the pipe became greater oil were boiling. This vapour was not than that at which the vapour was inflammable. He agreed with Dr condensed, the vapour would escape. Thomson as to the crackling noise, The pipe must be, he should conand the cause of it. He once thought sider, above 500 degrees of heat bethat oil boiled at 220 degrees, but he fore the vapour could escape. He afterwards found that it was the water could conceive a case where the creaescaping and falling again. Another tion of vapour below was more rapid experiment was made with oil exposed than its condensation above ; and the to a heat of about 400 deg. for 29 effect, in time, would be that some of days. When it reached 560 deg, a va- it should escape, and perhaps at a pour was geen to arise. At 575 a va.

somewhat lower temperature. pour came off, consisting of aqueous Re-examined. He could conceive matter and oil. At 610 deg. vapour that from a vessel of water the steam came, which burnt, accompanied with might escape at the end of the tube, gas, which, being carbonic, did not at a heat of 212 degrees. This could burn, but extinguished fame. The not be the case with oil, unless it were vapour, at 575 degrees, flashed a little, elevated to between 600 and 700 deg.; but he could not say whether it burnt it would then be in the same predica. continuously. The last oil was heated ment as water in a vessel at 212 deg. in a digester. This experiment was If the melting point of lead was 612, made in June last. As to new oil, he it would melt before this effect could never got any vapour or gas at any be produced. temperature below 600 deg. In old Mr Parke examined by the SOLICIoil, in an open vessel, some inflammable TOR-GENERAL.-Witness had all his vapour was obtained at 550, but no life applied himself to the study of gas. The vapour was not continuously chemistry. He had examined the apinflammable. The tube from which paratus, a model of which was now the vapour came in the second experi. exhibited, for the purpose of giving ment (in June last) was only six inches evidence on the last trial; and he had long. Mr Brande fully concurred in made many experiments, in order to asthe opinion of Dr Thomson, as to certain the inflammable qualities of oil. the new mode of refining sugar be. In his judgment the new mode of coming much less dangerous than the com- municating heat to sugar was less dan. mon. There was much less danger in gerous than the old. He apprehendoil heated to a high temperature than ed that it was absolutely impossible sugar to the same temperature. There that danger could arise to the building would be no danger from oil at 450 or from the new apparatus. 500 degrees, but from sugar, at such Michael Ferriday.--Had for a contemperatures, there would be immi- siderable time been engaged in the stunent danger. On the whole, as far as dy of chemistry, and had assisted at his experience went, he considered the some of the experiments of Sir H. plan decidedly superior.

Davy. Mr Wilson's plan was well Cross-examined.-He conceived that understood by him, and he certainly if vapour rose up into the pipe, it considered it to be much more danwould fall down again. That would gerous than the ordinary method of certainly depend on the temperature refining sugar. During the last two of the pipe. The pipe would of years he had himself, and in company course become warmer each time the with other gentlemen, made various vapour went up; and if the tem experiments on heated oil. The first

was made on a quantity of 24 gallons, lor and Mr Wilkinson were present. put into a copper 15 feet by 14, and After the fire was put out, the ebulliafter it had been heated upwards of tion continued for a considerable time. 20 days. The boiler was of a circular He tried a small quantity of the same shape, and the top of it therefore con- oil at home-it emitted vapour at 410 vex. A thermometer was put in nearly degrees, and at 480 degrees exploded at the bottom, and another towards with a brilliant combustion. The first the top of the boiler. It had also a experiment was made in the month of hood and a tube, or vent-pipe. He February, and two subsequent ones soon perceived that oil became inflam. were made in the following April. At mable in a very different degree after the first a steam-bin was filled with it had been once subjected to the ac- vapour in 16 seconds, and ultimately tion of fire. By repeated distillation it took fire ; a barrel also was inverted acquired properties altogether new : it over the apparatus, and its sides were produced a matter which was called scorched, although the flame went out. aptha, and became a volatile instead of [This barrel was afterwards produced a fixed subject. His meaning was, that in Court ; it had been taken, at the it arose into vapour much sooner, and time of the experiment, in rather a wet he had procured oil which would rise state, from an adjoining yard.] Hehad into vapour at the ordinary tempera- not examined the oil farther than to ture of the atmosphere, and which ascertain that it contained no sulphu. would burst into fame on the applica. ric acid. On the next experiment the tion of a lighted taper. This was call. vapour ignited at the degree of 486. ed explosion in chemistry ; but it took He had also examined the effect of fire place without noise, or, at least, de- on sugar, which he found to become tonation. His first experiment had for quite another substance when so deits object to discover whether oil composed. With white sugar, howe would yield these inflammable gases ever, it required a heat of 430 degrees, at the heat of 360 degrees, and after in a metallic pan, to alter it. This having been previously heated 22 se- might be accomplished, with coarse veral times. In a glass retort, he found moist sugar, at a heat of 230, but he it would give out such vapours at that had not ascertained whether it was in. point; and when tried on the larger flammable. He felt perfectly confiscale in a boiler, it did so at the degree dent that oil, used as it was in the proof 410. It arrived at this degree of cess of the plaintiffs, would be renderheat in about ten minutes. He collect. ed volatile, and liable to be very rapided the vapours in a pan, and a light ly heated. It would remain in a state caused the atmosphere in it to burn. of ebullition for two hours sometimes, In 20 minutes, and at the deg. of 460, after the fire was withdrawn. The the oil boiled over. The vapours as- witness, after describing several further cended in jets and spirits, through a experiments, producing similar results, pipe two feet high, and placed above declared his opinion, founded on these the apparatus. In the boiling state, a reasons, that the process in question thick scum formed on the surface, as was dangerous, both in a high and a on boiling milk, and would run over in low state of the atmosphere. time, as in the instance to which he Mr Bostock is Chemical Lecturer in alluded, when it fowed over in the Guy's Hospital. He was of opinion, and they were obliged to that, by the introduction of the new throw water on it. This took place in plan of refining sugar, a degree of daaWhitecross-street, and when Mr Tay- ger was incurred, which was in no de gree counterbalanced by the danger it perature in different parts of the ves. removed. He had not given very much sel. He thought that after the oil had attention to this particular subject been for some time kept at 360, any himself, but, from all he saw, this was accession of heat would be dangerous. his opinion. From all he saw since In the hands of such persons as usual. the last trial, his opinion of the danger ly attended furnaces, all those dangers of the new process was very much would be increased, because they would strengthened. The greatest degree of not be on their guard. Witness had danger arose from the difficulty of re- listened to Mr Ferriday; had attend. straining the temperature of oil at a ed some of his experiments: he took certain height, the same degree of heat notes at the same time, and concurred being applied, and also by the change with him in his deductions from them. which oil experiences, by being kept

He did not measure the heat of the for a long period at a temperature of fires used on those occasions. It was 360. Prepared oil (oil used in this difficult to measure the heat of fires way) acquired a property of giving exactly. He could not doubt but that out vapour at a lower temperature than the quality of oil was changed by benew oil would do. Another cause of ing exposed for a length of time to danger was the uncertainty of the ef. 360 degrees of heat. This change fects. We really, he thought, were consisted in its being capable of emitnot sufficiently masters of the subject ting vapour at a lower temperature to use oil as an agent in this way. He than common fresh oil. This would was asked his opinion of this appara- depend on the rapid accession of heat. tus before he saw it, and he gave it- He saw the experiments at Messrs that it was dangerous, for the reasons Severn's, by Mr Parkes and others, he now mentioned. It was dangerous on the 9th of December; he took notes 80 to use oil in a sugar. house, without em when he went home, He was having made previous experiments on informed that the oil he saw used had it. At first he was not aware that oil been exposed to a heat of 360 degrees long exposed to the action of heat for 35 days; but that it had been diswould emit inflammable vapour at so continued for some time, and renewed low a temperature ; but before he within the last four days. He arrived knew this, he gave the opinion men. at half past 12, and, on the premises, tioned, on the generally received opi- was told that the fire had been lit unnion that oil would emit a gas at a der the boiler at 9. The boiler was a temperature of 600. He also thought fac simile of the one used in the new that danger arose from the very great apparatus. The fire was moderate, difficulty of checking the heat beyond and the thermometer stood at 360 dea certain degree by any means inde- grees. It was opened at top, and a pendently of the constant attention of lighted taper put in ; but no vapour the workmen. Another cause of dan- was perceptible. Fuel was then add. ger was the risk of the vessel leaking, ed, and in 25 minutes the temperature and the oil dropping into the fire, and was raised to 376. The vapour did acting as fuel ; and, as connected with not light even then. There was then this, the danger of the oil in the ves. a mixture made of the vapour which sel becoming reduced by such means, the vessel contained, with the common so as to become heated suddenly, the air, but there was no combustion. He same fire being continued under it. then saw the old boiler, but it did not Another circumstance which produced appear rent or burst. The experiments some danger, was the difference of tem- he saw were not contradictory to those

« AnteriorContinua »