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 A HISTORY OF CORNWALL the manufacture of dynamite (No. i), blasting gelatine, gelatine-dynamite, and gelignite ; (2) Acid Works ; (3) Nitrate of Lead Department ; (4) Artificial Manure Works; (5) Engineering Department. By means of the recently opened railway line between Newquay and Chacewater the factory has been brought into direct com- munication with the Great Western Railway system. It will be observed that this factory, unlike that at Hayle, does not engage in the manufacture of explosives required for the pur- poses of ammunition. The manufacture of safety fuse at Tucking- mill demands something more than a passing notice, not only because it is the largest industry of its kind, but also because the inventor of the safety fuse was a Cornishman born in that neighbourhood. The frequent accidents result- ing from the use of explosives in tin and copper mining, and chiefly owing to the uncertain duration of the time between the lighting of the rush or quill and the exploding of the charge, led Mr. William Bickford in or about 1830 to turn his thoughts towards the invention of some method whereby blasting operations could be conducted with the minimum of risk to the miner. Mr. Bickford's motives were purely philanthropic; it remained for his successors to turn his invention into an extensive and legiti- mate commercial enterprise. On 6 September, 1831, Mr. Bickford took out his first patent for the ' Miners' Safety Fuse.' His object was to provide a protected core of powder, thin and continuous, along which the fire might travel slowly at a uniform and determinate rate of speed. This result he obtained by causing a number of jute threads, passed through an orifice and stretched by means of a weight attached to their extremities, to rotate slowly while, at the same time, a small current of fine powder fell into the tube thus formed, and was retained therein as a slender core. To use his own words in the specification of his process : I embrace in the centre of my fuse, in a con- tinuous line throughout its whole length, a small portion, or compressed cylinder, or rod of gun- powder, or other proper combustible matter pre- pared in the usual pyrotechnical manner of fire- work for the discharging of ordnance ; and which fuse so prepared I afterwards more effectually secure and defend by a covering of strong twine made of similar material, and wound thereon, at nearly right angles to the former twist, by the operation which I call countering, hereinafter described ; and I then immerse them in a bath of heated varnish, and add to them afterwards a coat of whiting, bran, or other suitable powdery substance, to prevent them from sticking together or to the fingers of those who handle them ; and I thereby also defend them from wet or moisture or other deterioration, and I cut off the same fuse in such lengths as occasion may require for use ; each of these lengths constituting when so cut off a fuse for blasting of rocks and mining, and I use them either under water or on land, in quarries of stone and mines for detaching portions of rocks, or stone or mine, as occasions require, in the manner long practised by, and well known to miners and blasters of rocks. Previous to the invention of safety fuse the devices for conveying the fire to the charge were of the most crude and primitive description. Sometimes a small trail of fine gunpowder from the charge to an extemporized slow-match, such as impregnated paper ; sometimes quills plucked from geese, filled with fine grain powder and lengthened where needful by the insertion of one quill into another ; while, oftener still, rushes were used, the rush having been first split, the pith scooped out, its place filled with powder, and the two halves bound together again by fine string. Mr. Bickford's invention has been well described as ' the very best means of blasting ever devised, combining certainty, economy, and safety.' 1 Numerous and important improvements have since been effected by the inventor's successors, resulting in the adoption of Bickford's safety fuse throughout the world. It has for many years been used by the English War Office, Admiralty, and other Government departments both at home and in the colonies; whilst its adoption by foreign governments and by foreign engineers and miners has led the proprietors to establish many factories on the continents of Europe, America, and Australia. Of the im- provements introduced within the last twenty years, the most important has been an ingenious device whereby the danger resulting from the use of a naked light or spark, for the purpose of igniting the fuse, has been completely obviated. By means of this ' Colliery Fuse and Safety Lighter,' blasting operations can be performed with safety in collieries and mines where inflam- mable gases are present, both the ignition and combustion of the fuse being effected without the emission of any spark or flame to the sur- rounding atmosphere. Another invention worthy of note is the volley-firer and instantaneous fuse, by means of which several charges can be fired simultaneously, and a greater effect obtained than if the same charges were fired independently. To the late Major John Soloman Bickford, and to the late Dr. George Smith, antiquary and historian, who married the inventor's daughter, belongs the credit of laying the foundations of safety fuse as a commercial undertaking. They directed its manufacture throughout their lives, and were succeeded by the inventor's three grandsons, the late Mr. Bickford Smith, M.P., Sir George J. Smith of Treliske, and Mr. H. Arthur Smith, M.A., Barrister-at-law. With the two latter are now associated four great- grandsons of Mr. Bickford. To Mr. Thomas 1 Dr. Ure's Dictionary of Arts, Manufactures and Mines, p. 5Z7- 516