1816.] Sir H. Davy on preventing Explosions in Coal Mines, apertures, open in the glass vessel: but the mixture in the bladder did not explode: and by pressing some of it into the glass vessel, so as to make it replace the foul air, and subjecting it to the electric spark, repeated explosions were produced, proving the perfect security of the safety apertures, even when acted on by a much more powerful explosion than could possibly occur from the introduction of air from the mines. 43 must be its depth, or the less its diameter to render it safe. I did not perceive any difference in these experiments, when the metals of the apertures were warmed by repeated explosions: it is probable, however, that considerable elevation of temperature would increase the power of the aperture to pass the explosion ; but the difference between the temperature of flame, and that marked on our common mercurial scale, is so great, that the addition of a few degrees of heat probably does not diminish perceptibly the cooling power of a metallic surface, with regard to flame. These experiments held good, whatever were the proportions of the explosive mixture, and whatever was the size of the glass vessel, (no one was ever used containing more than a quart,) provided as many as 12 By diminishing the diameter of the air metallic tubes were used of one-seventh of canals, their power of passing the explosion an inch in diameter, and two inches and a is so much diminished that their depth and half long; provided the circular metallic circumference may be brought extremely canals were one-twenty-fifth of an inch in low. I found that flame would not pass diameter, 1 of an inch deep, and at least through a canal of the one-seventieth of an two inches in circumference; or provided inch in diameter, when it was a quarter of the wire gauze had apertures of only of an inch deep, and forming a cylinder of an inch. When twelve metallic tubes were only a quarter of an inch in circumference ; employed as the medium of communication, and a number of apertures of of an inch one-seventh of an inch in diameter and an are safe when their depth is equal to their inch long, the explosion was communicated diameter. It is evident from these facts, by them into the bladder. Four glass tubes that metallic doors, or joinings in lamps, of the one-tenth of an inch in diameter and may be easily made safe by causing them to two inches long, did not communicate the project upon and fit closely to parallel meexplosion; but one of this diameter and tallic surfaces. length produced the effect. The explosion was stopped by a single tube one-twentyeighth of an inch in diameter, when it was three inches long, but not when it was two inches long. The explosion was stopped by the metallic gauze of when it was placed between the exploding vessel and the bladder, though it did not present a surface of more than half a square inch, and the explosive mixture in the bladder in passing through it to supply the vacuum produced in the glass vessel, burned on the surface exposed to the glass vessel for some seconds, producing a murmuring noise. A circular canal one-twenty-fifth of an inch in diameter, and an inch and a half in circumference, and 1 of an inch deep, communicated explosion; but four concentric canals, of the same depth and diameter, and of which the smallest was two inches in diameter, and separated from each other only by their sides, which were of brass,and about one-fortieth of an inch in thickness, did not suffer the explosion to act through them. It would appear then, that the smaller the circumference of the canal, that is, the neater it approaches to a tube, the greater These results appear at first view contradictory to those mentioned in page 40. But it must be kept in view, that the first set of experiments were made in tubes open in the air, and the last in tubes exposed to the whole force of air explosion, and connected only with close vessels filled with explosive rbixtures. Longitudinal air canals of metal may, I find, be employed with the same security as circular canals; and a few pieces of tin-plate soldered together with wires to regulate the diameter of the canal, answer the purpose of the feeder or safe chimney as well as drawn cylinders of brass. A candle will burn in a lantern or glass tube made safe with metallic gauze, as well as in the open air: I conceive, however, that oil lamps, in which the wick will always stand at the same height, will be preferred. But the principle applies to every kind of light, and its entire safety is demonstrated, When the fire-damp is so mixed with the external atmosphere as to render it explosive, the light in the safe-lantern or lamp will be extinguished, and warning will be given to the miners to withdraw from, and to ventilate that part of the mine. If it be necessary to be in a part of the mine where the fire-damp is explosive, for the purpose of clearing the workings, taking away pillars of coal, or other objects, the workmen may be lighted by a fire made of charcoal, which burns without flame, or by the steel mill, though this does not afford such entire security from danger as the char coal fire. It is probable, that when explosions occur from the sparks from the steel mill, the mixture of the fire-damp is in the proportion required to consume all the oxygen of the air, for it is only in about this proportion that explosive mixtures can be fired by electrical sparks from a common machine. 44 Sir H. Davy on preventing Explosions in Coal Mines. As the wick may be moved without communication between the air in the safe-lantorn or lamp in the atmosphere, there is no danger in trimming or feeding them; but they should be lighted in a part of the mine where there is no fire-damp, and by a person charged with the care of the lights; and by these inventions, used with such simple precautions, there is every reason to believe a number of lives will be saved, and much misery prevented. Where candles are employed in the open air in the mines, life is extinguished by the explosion; with the safe-lantern or safe-lamp, the light is only put out, and no other inconvenience will oc cur. Among various plans for preventing accidents from the fire-damp, it has been proposed to burn the fire-lamp in the mine; but this will only render the ventilation more difficult; for there will be less respirable air in the residuum of the combustion than in the mixed gas, and the ventilation must be greater to free the mine from the choke damp so generated, than from the original fre-damp. It does not appear, from what I have Fig. 1. [Feb. 1, learned from the miners, that breathing an atmosphere containing a certain mixture of fire-damp near or even at the explosive point, is attended with any bad consequence. I ascertained that a bird lived in a mixture of equal parts of fire-damp and air; but he soon began to shew symptoms of suffering. I found a slight head-ache produced by breathing for a few minutes an explosive mixture of fire-damp and air; and if merely the health of the miners be considered, the fire-damp ought always to be kept far below the point of its explosive mixture. Miners sometimes are found alive in a mine after an explosion has taken place: this is easily explained, when it is considered that the limitation is fixed to a particular spot, and that it mixes the residual air with much common air; and supposing 1 of fire damp to 13 of air to be exploded, there will still remain nearly of the original quantity of oxygen in the residual gas; and in some experiments, made sixteen years ago, I found that an animal lived, though with suffering, for a short time, in gas containing 100 parts of azote, fourteen parts of carbonic acid, and seven parts of oxygen. Fig. 2. Fig. 1. Represents the safe-lantern, with its air feeder and chimney furnished with safety metallic canals. It contains about a quart of air. The sides are of horn or glass, made air tight by putty or cement. A. is the lamp through which the circular feeding air canals pass; they are three concentric A 0000000000000 B. hollow cylinders, distant from each other ✈ of an inch the smallest is 24 inches in circumference; their depth is two inches. is the chimney, containing 4 such canals, the smallest 2 inches in circumference. above it is a hollow cylinder, with a cap to prevent dust from passing into the chimney. 1816.] New Acts of Parliament. C. is the hole for admitting oil, D. is a long canal containing a wire by which the wick is moved or trimmed. E. is the tube forming a connexion between the reservoir of oil and the chamber that supplies the wick with oil. F. is the rim round the bottom of the lantern to enable it to bear motion. Fig. 2. A metallic gauze safe lamp. AAA. Screens of metallic gauze or flame sieves. BB. Wires for trimming the wick.* The lamps burn brighter the higher the chimney. From my experiments it appears, that a mere narrow throat or opening to the metallic part of the chimney, is sufficient to prevent explosions from passing through the lamp, supposing them possible; but with the safety canals or metallic gauze in the chimney the security is absolute. The circular canals and the apertures covered with metallic gauze, are so much superior to tubes in practical application, that I have no doubt of their being generally used; I have therefore given no sketch of the first safe lantern I had constructed with tubes; but substituting tubes for canals it is exactly the same as that represented fig. 1. APPENDIX. 1. In the beginning of my inquiries I had another close lantern made, which may 45 be called the fire valve lantern. In this, the candle or lamp burns with its full quantity of air, admitted from the aperture below, till the air begins to be mixed with firedamp; when, as the fire-damp increases the flame, a thermometrical spring at the top of the lantern, made of brass and steel, riveted together, and in a curved form, expands, moves a valve in the chimney, diminishes the circulation of air, and extinguishes the flame. But I did not pursue this invention after I had discovered the properties of the fire-damp, on which the safe lantern is founded. 2. The safety of close lamps or lanterns may probably be likewise secured by sieves made of asbestus, or possibly even hair or silk, placed over the air apertures: but metallic gauze will be necessary above in the chimney. I have little doubt but that windows of fine metallic gauze may be used for giving light in lanterns, with perfect security; perhaps for the chimney it may be worth while to have fine plated silver wire gauze made. 3. The expansive powers of the fire-damp' during its explosion are so small as to render no precautions, with respect to the thickness of the glass or horn in the lamps or lanterns, necessary. NEW ACTS, PASSED IN THE THIRD SESSION OF THE FIFTH PARLIAMENT OF THE UNITED KINGDOM OF GREAT BRITAIN AND IRELAND.-55 GEO. III. (1815.) [The figure which follows the date of each Act, denotes the number of sheets of which it consists: each sheet is sold for THREE-PENCE.] LXXX. An Act to provide for the Collection and Management of Stamp Duties on Pamphlets, Almanacks, and Newspapers in Ireland. June 14.-3. One copy of every pamphlet to be lodged at the Stamp Office. Penalty for not paying duty to be 401 and forfeiture of copyright. Venders of unstamped almanacks to forfeit 51. for each copy. Every hand-bill containing more than one advertisement to be deemed a newspaper, The printer's name and place of abode to be affixed to all newspapers and pamphlets under a penalty of 101. Affidavits of proprietorship of newspapers to be made before the Commissioners of Stamps, The ingenious author has given enlarged representations of different parts of his lamps; also of a safe lamp having a glass chimney covered with a tin plate, and the safety appertures in a cylinder with the covering above; of an argand lamp of similar construction, and of a glass tube furnished with flame sieves in which a common candle may may be burned. As however the general principle is the same in all, we have thought 'that the figures given above would afford a sufficient illustration of it. EDITOR. and to be evidence in any proceedings at law. Copies of newspapers to be lodged at the Stamp Office, which shall be evidence against the proprietors. Copies of second editions to be lodged in like manner as the first. Printers outlawed for any criminal of fence, or who may receive judgment for a traitorous or seditious libel, shall not be supplied with stamps. Printers becoming bankrupt, or non compos mentis, shall, no longer be entitled to print newspapers. Persons having unstamped newspapers in their possession shall be liable to a penalty of 101. and the printer, proprietor, or publisher, to a penalty of 201. for each newspaper so unstamped. Printers supplying others with stamps to forfeit 401. and persons using stamped paper so furnished to be liable to the like penalty. Duty on advertisements to be paid monthly. Printing materials may be seized for duty. The operation of this act to commence July 5, 1815. LXXXI. An Act to repeal the several Acts for the Collection and Management of Stamp Duties in Ireland, and to make more effectual Regulations for col lecting and managing the said Duties in general. June 14.-8. 46 New Acts of Parliament. LXXXII. An Act to grant Duties of Customs, and to allow Drawbacks and Bounties on certain Goods, Wares, and Merchandize imported into and exported from Ireland, in lieu of former Duties, Drawbacks, and Bounties; and to make further Regulations for securing the Duties of Customs in Ireland. June 14.-3. LXXXIII. An Act to regulate the Payment of the Duties of Customs on Foreign Goods imported into Great Britain from Ireland, or into Ireland from Great Britain; and of the Drawbacks on the Exportation of Goods the Growth, Produce, or Manufacture of Great Britain or Ireland, having been imported into either country from the other. June 14.-1. When goods imported into either country from the other shall be exported, the exporter shall be allowed a drawback equal to the duty. Foreign wines in bottles or flasks in packages containing six dozen quart bottles or flasks may be imported into either country from the other. LXXXIV. An Act to amend so much of an Act of the 33rd year of his present Majesty as relates to fixing the limits of the towns of Calcutta, Madras, and Bombay; and also so much of an Act of the 39th and 40th of his present Majesty as relates to granting Letters of Administration to the Effects of Persons dying intestate within the several Presidencies in the East Indies to the Registrar of the Ecclesiastical Courts; and to enable the Governor in Council of the said Presidencies to remove Persons not being British Subjects; and to make Provision for the Judges in the East Indies in certain Cases. June 14.-2. LXXXV. An Act to amend and continue for One Year and until Twelve Months after the Termination of the present War by the Ratification of a Definitive Treaty of Peace, Two Acts of his present Majesty for enabling Subjects of Foreign States to enlist and serve as Soldiers in his Majesty's Service, and to enable his Majesty to grant Commismissions to Subjects of Foreign States to serve as Officers under certain Restrictions. June 14.-1. LXXXVI. An Act to continue until the 25th day of March, 1820, an Act made in the 46th year of his present Majesty for permitting the Importation of Masts, Yards, Bowsprits, and Timber for Naval Purposes from the British Colonies of North America. June 14.-1. LXXXVII. An Act to relieve certain Foreign Vessels resorting to the Port of London in respect of Pilotage; and to [Feb. 1, regulate the Mode of Payment of Pilotage on Foreign Vessels in the said Port. June 14.-1. LXXXVIII. An Act to amend an Act of the last Session of Parliament for rendering more easy and effectual Redress for Assaults in Ireland. June 14. -1. The Grand Jury at assizes may make presentment for costs adjudged at Sessions under the act 54 Geo. III. c. 181. LXXXIX. An Act to amend an Act of the 53rd Year of his Majesty's Reign, for making Regulations for the building and repairing of Court Houses and Sessions Houses in Ireland. June 14.-1. XC. An Act to explain an Act made in the Parliament of Ireland in the 32nd year of his Majesty's Reign, relative to inland Navigations there, so far as relates to the Limitation of Actions against Canal Companies and others. June 14.-1. Costs and Charges to Prosecutors and XCI. An Act for the Payment of Witnesses in Cases of Felony in Ireland. June 14.-1. XCII. An Act to amend an Act of the 50th year of his present Majesty's Reign relating to Prisons in Ireland, so far as concerns Contracts for building or repairing such Prisons. June 14.-1. XCIII. An Act to repeal the Duties payable on, and the Permission to enter for Home Consumption, Silk Handkerchiefs imported by the East India Com pany. June 14.-1. XCIV. An Act to continue and amend several Acts relating to the British White Herring Fishery. June 14. -4. The bounty on exportation repealed and that on cured herrings increased from 2s. to 4s. per barrel, which must contain, exclusive of salt and brine, according to the mode of package, from 212 lbs. to 235 lbs, weight of fish at least. XCV. An Act to repeal the Duties payable on the Importation into Great Britain of solid Vegetable Extract fron Oak Bark and other Vegetable Substances used in the Tanning of Leather; and to grant a Duty in lieu thereof. June 14.-1. The duty imposed by this act is 3s. per cwt. XCVI. An Act to grant a further Sum of Money for purchasing an Estate to accompany the Title of Earl Nelson, and also to amend Two Acts of the 46th and 53rd years of his Majesty's Reign for making such Purchase. June 14.-3. In addition to the sum of 90,000l. granted by former acts, 9,000l. is to be paid out of the Consolidated Fund to the Trustees, and the whole to be expended in the purchase and repair of the manor and mansion of Standlynch in Wiltshire, and in the enfranchisement of copyhold premises belonging to that estate. XCVII. An Act to grant to the Judges of the Commissary Court of Edinburgh a fixed Salary in place of their present Salary and certain Fees and Payments. June 14.-1. All fees to judges to cease, and the judges of the Commissary Court to receive 600l. a year each. 47 Committee on the Downpatrick Election to re-assemble and to suspend the Transmission of Warrants and other Proceedings for the Appointment of Commissioners to examine Witnesses in Ireland. June 14.-1. XCIX. An Act to make further Provisions for collecting and securing the Duties of Excise on Malt made in Ireland. June 22.-2. C. An Act to provide for the Collection and Management of Stamp Duties payable on Bills of Exchange, Promissory Notes, Receipts, and Gaine Certificates, XCVIII. An Act to enable the Select in Ireland. June 22.-3. ORIGINAL POETRY. THE BATTLE OF WATERLOO, Written at Brussels, June, 1815. To save our country WELLINGTON was His glorious deeds her annals shall adorn. cause, He fought for honour and the world's applause. Cool and deliberate, yet with ardor fir'd, With thoughts of victory his soul inspir'd; The gallant Chief, near yon adjoining wood, Firm as a rock, 'mid danger nobly stood; Gaz❜d on his men, then pass'd from front to rear, The ranks resounding with a treble cheer; From Frichmont's heights to Gaumont's Britain's heroic sons the shock sustain, Thrice did Napoleon head the fierce attack, And thrice the British squadrons drove him back; Till maul'd and feather'd in the glorious fight, |