THE MAKING OF MODERN MONOLITHS.

Northland Age, Volume 4, Issue 3, 3 September 1907, Page 2

THE MAKING OF MODERN MONOLITHS.

' * People often &ak whether modem man could have handled the monolithic masses which the ancients worked into such monumental erections as the Pyramids of Ghizeh, the tremendous otairwavs of Persepolis, ♦.he trilithoijs of Stonehenge, and ihe Standing Stonos of Stennis. One might quote by way of reply the transier of ’.Cleopatra's Needle from to the (Thames Embankment, or thq greater hut less known instance of the architrave of the uncompleted National Monument upon the Carlton Hill in Edinburgh. The latter was cut out of Craiglcith Quarry in 1823, as a solid block 136 feet long by 20 feet broad, estimated to weigh 15,000 tons of limestone rock. As a whole it was claimed to be the greatest stone ever excavated. The larger portion went to the monument, and the rest to Buckingham Palace. But as a matter of fact the moderns have not, antil quite lately, been able to handle such masses with success. The inert} carriage of Cleopatra’s Needle nearly ended in disaster, and it may be doubted whether the engineers of the date (1878) when it was brought to England, could have extracted it from its native quarry as* the ancients had done. The outlay upon the Edinburgh stone was so enormous that it was almost the last laid upon this great Monument, which was therefore never 1 carried further, and has now remained unfinished for over eighty years. Yet it was intended to be as nearly a reproduction of the Parthenon at. Athens, which the Greeks duly completed, notwithstanding its monolithic character. The explanation of course, is that they, in common with all othor ancient peoples who handled such masses, had labour at their disposal such as the moderns have not. They could turn on hundreds of men for years to quarry a single block, employ a whole tribe to haul it, inch by inch, to its site, and engage an army in its erection—all yvithout wages in our acceptance of the word. It is not surprising that as the value of human life and time come to be bettor understood monolithic building ceased ; remaining

practically forgotten for several milienniums.

Now, however, it is being revived by several marvellous applications of machiuery to work which would formerly have employed whote nations. Of these one of the most wonderful Is a column cutting machine employed mostly in Belgium. It does its work in the most direct manner possible, for it carves the cylinders out of the solid rock within the quarry Itself. An iron or steel revolving cylinder, electrically driven, is placed above the spot selected for the cutting The outer circumference of its lower surface is armed with a series of saw-like teeth, and these as the cylinder goes round at tho rate of about fifty revolutions per minute, eat into the stone, thus carving out the column as the cylinder sinks. When the first section of the latter has disappeared into the rock another is superimposed upon it. When the desired depth is reached the core is broken off at the bottom by wedges driven Into the groove cut by the knives—which, with tho cylinders, have been previously withdrawn—and is hoisted out by a power windlass erected over the top. In this way monolithic shafts up to fifty feet long by ten feet in circumference can be cut by half a dozen men in as many days as they would have occupied hundreds of labourers for years in ancient times. To extract square or angled monoliths, the channeling machine has been invented. Originally it was most extensively employed in quarries at Vermont, U.S.A., where it was found that blasting tended to destroy a large proportion of the valuable stone. It consists of a minaturo locomotive running upon rails laid upon the quarry floor and furnished underneath or at the sides, with a number of steel cutting tools which score out the rock to the desired depth as the machine runs backwards and forwards until the area under treatment is carved into blocks which are fast only at the bottom To free them one block is blasted out entirely in order to gain access to the lower portions of the remainder which are then split off by light charges of explosives placed in hoies drilled underneath. By this system the only limitation of the size of monoliths is the possibility of moving them from their native bed, and this, of course, depends largely upon the situation and levels of each individual quarry. But with recently invented hydraulic appliances there woulld he no insurmountable difficulty In dealing in masses even larger than Cleopatra's Needle, which weighs 168 tons, without its base. Increase in knowledge of high explosives has also tended to revive tho making of monoliths. Many of those created from the granite of Aberdeenshire have been so obtained. The process is necessarily a much rougher one than that which depends upon machinery. As much as 50,000 tons of material may be displaced at one blast in order to obtain a comparatively small number of blocks of special size. Those receive a preliminary shaping by hand, and are then transported to machine shops for further treatment. If the monoliths are required for engineering w’orks they are merely trimmed there, but if are destined for monumental or architectural purposes they are subjected to a series of marvellous machines which, cut, polish, and carve the hard, granitic surfaces of the monsters by means of electricity, water and air in pneumatic tools, as though the substance were chalk or cheese. These granite monoliths are even carved into statues —an art otherwise obselete since the Romans reigned in Egypt. Curiously enough, the same blasting process is now utilised to obtain monolithic blocks from Italian marble quarries, where the saw invented by Leonardo 4fta Vii¥i is still in use, and where Michael Ange)6 was wont to go to superintend the extraction of the raw material for his masterpieces by the most painful of hand labour. Nowadays the marble is blasted out above the valleys, into which it is permitted to drop whilst sounding horns warn tboas below to stand clear. The blocks that survive this treatment are rudely hewn into the form they are ultimately destined tojumume wdjheo

con; u»«r original weight or about nine tons being each subsequently reduced in England to their presently shapely proportions of about 16 feet by 7 feet circumference. The hugest of all modern monoliths are those of artificial stone, such as that, several thousand tons in weight Shich constitutes the chief foundation 1 the new harbour works at Gibraltar. The ancients knew nothing of any similar process, and it is hardly fair to compare the solid masses they handled with those we create by bag after bag of concrete. But enough has been said to show that in dealing with solid masses of naturall rock modern machinery is now equal to the strenuous physical labour which moved them when the world was thousands of years younger.—“ Weekly, Telegraph.”