Part 19

Hanging fire may be due to a cut, broken or damaged powder fuze, which may smoulder for some time before communicating fire to the charge. "Miss-fires," which also are of not infrequent occurrence with both ordinary and electric fuzes, are cases where explosion from any cause fails to take place. After waiting a sufficient length of time before approaching the charged hole, the miner carefully removes the tamping down to within a few inches of the explosives and inserts and fires another cartridge, the concussion usually detonating the entire charge. Sometimes another hole is drilled near the one which has missed. No attempt to remove the old charge should ever be made.

High tension electricity, generated by a frictional machine, provided with a condenser, was formerly much used for blasting. The bare ends of the fuze wires in the detonating cap are placed say 1/8 in. apart, leaving a gap across which a spark is discharged, passing through a priming charge of some sensitive composition. The priming is not only combustible but also a conductor of electricity, such as an intimate mixture of potassium chlorate with copper sulphide and phosphide. By the combustion of the priming the fulminate mixture in the cap is detonated. As these fuzes are more apt to deteriorate when exposed to dampness than fuzes for low-tension current, and the generating machine is rather clumsy and fragile, low-tension current is more generally employed. It may be generated by a small, portable dynamo, operated by hand, or may be derived from a battery or from any convenient electric circuit. The ends of the fuze wires in the detonating cap are connected by a fine platinum filament (fig. 11), embedded in a guncotton priming on top of the fulminating mixture, and explosion results from the heat generated by the resistance opposed to the passage of the current through the filament. Blasting machines are made in several sizes, the smaller ones being capable of firing simultaneously from ten to twenty holes. The fuzes must obviously be of uniform electrical resistance, to ensure that all the connected charges will explode simultaneously. The premature explosion of any one of the fuzes would break the circuit.

In the actual operations of blasting, definite rules for the proportioning of the charges are rarely observed, and although the blasts made by a skilful miner seldom fail to do their work, it is a common fault that too much, rather than too little, explosive is used. The high explosives are specially liable to be wasted, probably through lack of appreciation of their power as compared with that of black powder. Among the indications of excessive charges are the production of much finely broken rock or of crushed and splintered rock around the bottom of the hole, and excessive displacement or projection of the rock broken by the blast. In beginning any new piece of work, such waste may be avoided or reduced by making trial shots with different charges and depths of hole, and noting the results; also by letting contracts under which the workmen pay for the explosive. In surface rock excavation the location and determination of the depth of the holes and the quantity of explosive used, are occasionally put in charge of one or more skilled men, who direct the work and are responsible for the results obtained.

Blasting in surface excavations and quarries is sometimes done on an immense scale--called "mammoth blasting." Shafts are sunk, or tunnels driven, in the mass of rock to be blasted, and, connected with them, a number of chambers are excavated to receive the charges of explosive. The preparation for such blasts may occupy months, and many tons of gunpowder or dynamite are at times exploded simultaneously, breaking or dislodging thousands, or even hundreds of thousands, of tons of rock. This method is adopted for getting stone cheaply, as for building macadamized roads, dams and breakwaters, obtaining limestone for blast furnace flux, and occasionally in excavating large railway cuttings. It is also applied in submarine blasting for the removal of reefs obstructing navigation, and sometimes for loosening extensive banks of partly cemented gold-bearing gravel, preparatory to washing by hydraulic mining.

AUTHORITIES.--For further information on drilling and blasting see:--Callon, _Lectures on Mining_ (1876), vol. i. chs. v. and vi.; Foster, _Text-book of Ore and Stone Mining_, (1900), ch. iv.; Hughes, _Text-book of Coal Mining_ (1901), ch. iii.; H.S. Drinker, _Tunnelling, Explosive Compounds and Rock Drills_ (1878); M.C. Ihlseng, _Manual of Mining_ (1905), pp. 596-696; Kohler, _Der Bergbaukunde_ (1897), pp. 104-208; Daw, _The Blasting of Rock_ (1898); Prelini, _Earth and Rock Excavation_ (1905), chs. v., vi. and vii.; Gillette, _The Excavation of Rock_ (1904); Guttmann, _Blasting_ (1892); Spon's _Dictionary of Engineering_, art. "Boring and Blasting"; Eissler, _Modern High Explosives_ (1893), pts. ii. and iii.; Walke, _Lectures on Explosives_ (1897), chs. xix.-xxii. Also: _Proc. Inst. Civ. Eng._ (London), vol. lxxxv. p. 264; _Trans. Inst. Min. Eng._ (England), vols. xiv., xv. and xvi. (arts, by W. Maurice), vol. xxvi. pp. 322, 348, vol. xxiv. p. 526 and vol. xxv. p. 108; _Trans. Amer. Soc. Civ. Eng._, vol. xxvii. p. 530; _Trans. Amer. Inst. Min. Eng._, vol. xviii. p. 370, vol. xxix p. 405 and vol. xxxiv. p. 871; _South Wales Inst. Eng._ (1888); _Jour. Ass. Eng. Socs._, vol. vii. p. 58; _Jour. Chem. Met. and Mining Soc. of South Africa_, August 1905; _School of Mines Quarterly_, N.Y., vol. ix. p. 308; _Colliery Guardian_, April 15, 1898, and February 6, 1903; _Mines and Minerals_, February 1905, p. 348, January 1906, p. 259, and April 1906, p. 393; _Eng. and Mining Jour._, April 19, 1902, p. 552; _The Engineer_, February 24, 1905; _Elec. Rev._, June 9, 1899; _Eng. News_, vol. xxxii. p. 249, and August 3, 1905; _Gluckauf_, September 28, 1901, and July 5, 1902; _Osterr. Zeitschr. f. Berg- u. Huttenwesen_, May 18, 25, 1901, April 18, 1903 and November, 18, 1905; _Annales des mines_, vol. xviii. pp. 217-248. (R. P.*)

BLAUBEUREN, a town of Germany, in the kingdom of Wurttemberg, 12 m. W. of Ulm, with which it is connected by railway. Pop. (1900) 3114. It is romantically situated in a wild and deep valley of the Swabian Alps at an altitude of 1600 ft. and is partly surrounded by ancient walls. Of the three churches (two Evangelical and one Roman Catholic) the most remarkable is the abbey church (_Klosterkirche_), a late Gothic building dating from 1465-1496, the choir of which contains beautiful 15th century carved choir-stalls and a fine high altar with a triptych (1496). The choir only is used for service (Protestant), the nave being used as a gymnasium. The town church (_Stadtkirche_) also has a fine altar with triptych. The Benedictine abbey, founded in 1095, was used after the Reformation as a school, and is now an Evangelical theological seminary. There are two hospitals in the town.

BLAVATSKY, HELENA PETROVNA (1831-1891), Russian theosophist, was born at Ekaterinoslav, on the 31st of July (O.S.) 1831, the daughter of Colonel Peter Hahn, a member of a Mecklenburg family, settled in Russia. She married in her seventeenth year a man very much her senior, Nicephore Blavatsky, a Russian official in Caucasia, from whom she was separated after a few months; in later days, when seeking to invest herself with a halo of virginity, she described the marriage as a nominal one. During the next twenty years Mme Blavatsky appears to have travelled widely in Canada, Texas, Mexico and India, with two attempts on Tibet. In one of these she seems to have crossed the frontier alone in disguise, been lost in the desert, and, after many adventures, been conducted back by a party of horsemen. The years from 1848 to 1858 were alluded to subsequently as "the veiled period" of her life, and she spoke vaguely of a seven years' sojourn in "Little and Great Tibet," or preferably of a "Himalayan retreat." In 1858 she revisited Russia, where she created a sensation as a spiritualistic medium. About 1870 she acquired prominence among the spiritualists of the United States, where she lived for six years, becoming a naturalized citizen. Her leisure was occupied with the study of occult and kabbalistic literature, to which she soon added that of the sacred writings of India, through the medium of translations. In 1875 she conceived the plan of combining the spiritualistic "control" with the Buddhistic legends about Tibetan sages. Henceforth she determined to exclude all control save that of two Tibetan adepts or "mahatmas." The mahatmas exhibited their "astral bodies" to her, "precipitated" messages which reached her from the confines of Tibet in an instant of time, supplied her with sound doctrine, and incited her to perform tricks for the conversion of sceptics. At New York, on the 17th of November 1875, with the aid of Colonel Henry S. Olcott, she founded the "Theosophical Society" with the object of (1) forming a universal brotherhood of man, (2) studying and making known the ancient religions, philosophies and sciences, (3) investigating the laws of nature and developing the divine powers latent in man. The Brahmanic and Buddhistic literature supplied the society with its terminology, and its doctrines were a curious amalgam of Egyptian, kabbalistic, occultist, Indian and modern spiritualistic ideas and formulas. Mme Blavatsky's principal books were _Isis Unveiled_ (New York, 1877), _The Secret Doctrine, the Synthesis of Science, Religion and Philosophy_ (1888), _The Key to Theosophy_ (1891). The two first of these are a mosaic of unacknowledged quotations from such books as K.R.H. Mackenzie's _Royal Masonic Encyclopaedia_, C.W. King's _Gnostics_, Zeller's _Plato_, the works on magic by Dunlop, E. Salverte, Joseph Ennemoser, and Des Mousseaux, and the mystical writings of Eliphas Levi (L.A. Constant). _A Glossary of Theosophical Terms_ (1890-1892) was compiled for the benefit of her disciples. But the appearance of Home's _Lights and Shadows of Spiritualism_ (1877) had a prejudicial effect upon the propaganda, and Heliona P. Blavatsky (as she began to style herself) retired to India. Thence she contributed some clever papers, "From the Caves and Jungles of Hindostan" (published separately in English, London, 1892) to the _Russky Vyestnik_. Defeated in her object of obtaining employment in the Russian secret service, she resumed her efforts to gain converts to theosophy. For this purpose the exhibition of "physical phenomena" was found necessary. Her jugglery was cleverly conceived, but on three occasions was exposed in the most conclusive manner. Nevertheless, her cleverness, volubility, energy and will-power enabled her to maintain her ground, and when she died on the 8th of May 1891 (White Lotus Day), at the theosophical headquarters in the Avenue Road, London, she was the acknowledged head of a community numbering not far short of 100,000, with journalistic organs in London, Paris, New York and Madras.

Much information respecting her will be found in V.S. Solovyov's _Modern Priestess of Isis_, translated by Walter Leaf (1895), in Arthur Lillie's _Madame Blavatsky and Her Theosophy_ (1895), and in the report made to the Society for Psychical Research by the Cambridge graduate despatched to investigate her doings in India. See also the article THEOSOPHY.

BLAYDES, FREDERICK HENRY MARVELL (1818-1908), English classical scholar, was born at Hampton Court Green, on the 29th of September 1818, being a collateral descendant of Andrew Marvell, the satirist and friend of Milton. He was educated at St Peter's school, York, and Christ Church, Oxford. He was Hertford scholar in 1838, took a second class in literae humaniores in 1840, and was subsequently elected to a studentship at Christ Church. In 1842 he took orders, and from 1843 to 1886 was vicar of Harringworth in Northamptonshire. During a long life he devoted himself almost entirely to the study of the Greek dramatists. His editions and philological papers are remarkable for bold conjectural emendations of corrupt (and other) passages. His distinction was recognized by his being made an honorary LL.D. of Dublin, Ph.D. of the university of Buda Pest and a fellow of the royal society of letters at Athens. He died at Southsea on the 7th of September 1908.

His works include:--Aristophanes: _Comedies and Fragments_, with critical notes and commentary (1880-1893); _Clouds, Knights, Frogs, Wasps_ (1873-1878); _Opera Omnia_, with critical notes (1886); Sophocles; _Oedipus Coloneus, Oedipus Tyrannus_ and _Antigone_ (in the Bibliotheca Classica, 1859); _Philoctetes_ (1870), _Trachiniae_ (1871), _Electra_ (1873), _Ajax_ (1875), _Antigone_ (1005); Aeschylus: _Agamemnon_ (1898), _Choephori_ (1899), _Eumenides_ (1900), _Adversaria Critica in Comicorum Graecorum Fragmenta_ (1890); _in Tragicorum Graec. Frag._ (1894), _in Aeschylum_ (1895), _in Varios Poetas Graecos et Latinos_ (1898), _in Aristophanem_ (1899), _in Sophoclem_ (1899), _in Euripidem_ (1901), _in Herodotum_ (1901); _Analecta Comica Graeca_ (1905); _Analecta Tragica Graeca_ (1906).

BLAYDON, an urban district in the Chester-le-Street parliamentary division of Durham, England, on the Tyne, 4 m. W. of Newcastle by a branch of the North-Eastern railway. Pop. (1881) 10,687; (1901) 19,617. The chief industries are coal-mining, iron-founding, pipe, fire-brick, chemical manure and bottle manufactures. In the vicinity is the beautiful old mansion of Stella, and below it Stellaheugh, to which the victorious Scottish army crossed from Newburn on the Northumberland bank in 1640, after which they occupied Newcastle.

BLAYE-ET-STE LUCE, a town of south-western France, capital of an arrondissement in the department of Gironde, on the right bank of the Gironde (here over 2 m. wide), 35 m. N. of Bordeaux by rail. Pop. (1906) of the town, 3423; of the commune, 4890. The town has a citadel built by Vauban on a rock beside the river, and embracing in its enceinte ruins of an old Gothic chateau. The latter contains the tomb of Caribert, king of Toulouse, and son of Clotaire II. Blaye is also defended by the Fort Pate on an island in the river and the Fort Medoc on its left bank, both of the 17th century. The town is the seat of a sub-prefect, and has tribunals of first instance and of commerce and a communal college. It has a small river-port, and carries on trade in wine, brandy, grain, fruit and timber. The industries include the building of small vessels, distilling, flour-milling, and the manufacture of oil and candles. Fine red wine is produced in the district.

In ancient times Blaye (_Blavia_) was a port of the Santones. Tradition states that the hero Roland was buried in its basilica, which was on the site of the citadel. It was early an important stronghold which played an important part in the wars against the English and the Religious Wars. The duchess of Berry was imprisoned in its fortress in 1832-1833.

BLAZE (A.-S. _blaese_, a torch), a fire or bright flame; more nearly akin to the Ger. _blass_, pale or shining white, is the use of the word for the white mark on the face of a horse or cow, and the American use for a mark made on a tree by cutting off a piece of the bark. The word "to blaze," in the sense of to noise abroad, comes from the A.-S. _blaesan_, to blow, cf. the Ger. _blasen_; in sense, if not in origin, it is confused with "blazon" in heraldry.

BLAZON, a heraldic shield, a coat of arms properly "described" according to the rules of heraldry, hence a proper heraldic description of such a coat. The O. Fr. _blason_ seems originally to have meant simply a shield as a means of defence and not a shield-shaped surface for the display of armorial bearings, but this is difficult to reconcile with the generally accepted derivation from the Ger. _blasen_, to blow, proclaim, English "blaze," to noise abroad, to declare. In the 16th century the heraldic term, and "blaze" and "blazon" in the sense of proclaim, had much influence on each other.

BLEACHING, the process of whitening or depriving objects of colour, an operation incessantly in activity in nature by the influence of light, air and moisture. The art of bleaching, of which we have here to treat, consists in inducing the rapid operation of whitening agencies, and as an industry it is mostly directed to cotton, linen, silk, wool and other textile fibres, but it is also applied to the whitening of paper-pulp, bees'-wax and some oils and other substances. The term bleaching is derived from the A.-S. _blaecan_, to bleach, or to fade, from which also comes the cognate German word _bleichen_, to whiten or render pale. Bleachers, down to the end of the 18th century, were known in England as "whitsters," a name obviously derived from the nature of their calling.

The operation of bleaching must from its very nature be of the same antiquity as the work of washing textures of linen, cotton or other vegetable fibres. Clothing repeatedly washed, and exposed in the open air to dry, gradually assumes a whiter and whiter hue, and our ancestors cannot have failed to notice and take advantage of this fact. Scarcely anything is known with certainty of the art of bleaching as practised by the nations of antiquity. Egypt in early ages was the great centre of textile manufactures, and her white and coloured linens were in high repute among contemporary nations. As a uniformly well-bleached basis is necessary for the production of a satisfactory dye on cloth, it may be assumed that the Egyptians were fairly proficient in bleaching, and that still more so were the Phoenicians with their brilliant and famous purple dyes. We learn, from Pliny, that different plants, and likewise the ashes of plants, which no doubt contained alkali, were employed as detergents. He mentions particularly the _Struthium_ as much used for bleaching in Greece, a plant which has been identified by some with _Gypsophila Struthium_. But as it does not appear from John Sibthorp's _Flora Graeca_, edited by Sir James Smith, that this species is a native of Greece, Dr Sibthorp's conjecture that the _Struthium_ of the ancients was the _Saponaria officinalis_, a plant common in Greece, is certainly more probable.

In modern times, down to the middle of the 18th century, the Dutch possessed almost a monopoly of the bleaching trade although we find mention of bleach-works at Southwark near London as early as the middle of the 17th century. It was customary to send all the brown linen, then largely manufactured in Scotland, to Holland to be bleached. It was sent away in the month of March, and not returned till the end of October, being thus out of the hands of the merchant more than half a year.

The Dutch mode of bleaching, which was mostly conducted in the neighbourhood of Haarlem, was to steep the linen first in a waste lye, and then for about a week in a potash lye poured over it boiling hot. The cloth being taken out of this lye and washed, was next put into wooden vessels containing buttermilk, in which it lay under a pressure for five or six days. After this it was spread upon the grass, and kept wet for several months, exposed to the sunshine of summer.

In 1728 James Adair from Belfast proposed to the Scottish Board of Manufactures to establish a bleachfield in Galloway; this proposal the board approved of, and in the same year resolved to devote L2000 as premiums for the establishment of bleachfields throughout the country. In 1732 a method of bleaching with kelp, introduced by R. Holden, also from Ireland, was submitted to the board; and with their assistance Holden established a bleachfield for prosecuting his process at Pitkerro, near Dundee.

The bleaching process, as at that time performed, was very tedious, occupying a complete summer. It consisted in steeping the cloth in alkaline lyes for several days, washing it clean, and spreading it upon the grass for some weeks. The steeping in alkaline lyes, called _bucking_, and the bleaching on the grass, called _crofting_, were repeated alternately for five or six times. The cloth was then steeped for some days in sour milk, washed clean and crofted. These processes were repeated, diminishing every time the strength of the alkaline lye, till the linen had acquired the requisite whiteness.

For the first improvement in this tedious process, which was faithfully copied from the Dutch bleachfields, manufacturers were indebted to Dr Francis Home of Edinburgh, to whom the Board of Trustees paid L100 for his experiments in bleaching. He proposed to substitute water acidulated with sulphuric acid for the sour milk previously employed, a suggestion made in consequence of the new mode of preparing sulphuric acid, contrived some time before by Dr John Roebuck, which reduced the price of that acid to less than one-third of what it had formerly been. When this change was first adopted by the bleachers, there was the same outcry against its corrosive effects as arose when chlorine was substituted for crofting. A great advantage was found to result from the use of sulphuric acid, which was that a souring with sulphuric acid required at the longest only twenty-four hours, and often not more than twelve; whereas, when sour milk was employed, six weeks, or even two months, were requisite, according to the state of the weather. In consequence of this improvement, the process of bleaching was shortened from eight months to four, which enabled the merchant to dispose of his goods so much the sooner, and consequently to trade with less capital.

No further modification of consequence was introduced in the art till the year 1787, when a most important change was initiated by the use of chlorine (q.v.), an element which had been discovered by C.W. Scheele in Sweden about thirteen years before. The discovery that this gas possesses the property of destroying vegetable colours, led Berthollet to suspect that it might be introduced with advantage into the art of bleaching, and that it would enable practical bleachers greatly to shorten their processes. In a paper on chlorine or oxygenated muriatic acid, read before the Academy of Sciences at Paris in April 1785, and published in the _Journal de Physique_ for May of the same year (vol. xxvi. p. 325), he mentions that he had tried the effect of the gas in bleaching cloth, and found that it answered perfectly. This idea is still further developed in a paper on the same substance, published in the _Journal de Physique_ for 1786. In 1786 he exhibited the experiment to James Watt, who, immediately upon his return to England, commenced a practical examination of the subject, and was accordingly the person who first introduced the new method of bleaching into Great Britain. We find from Watt's own testimony that chlorine was practically employed in the bleachfield of his father-in-law, Mr Macgregor, in the neighbourhood of Glasgow, in March 1787. Shortly thereafter the method was introduced at Aberdeen by Messrs Gordon, Barron & Co., on information received from De Saussure through Professor Patrick Copland of Aberdeen. Thomas Henry of Manchester was the first to bleach with chlorine in the Lancashire district, and to his independent investigations several of the early improvements in the application of the material were due.

In these early experiments, the bleacher had to make his own chlorine and the goods were bleached either by exposing them in chambers to the

## action of the gas or by steeping them in its aqueous solution. If we