Part 20 (1/2)
Dr. Lilienthal, a German, was the first to try scientific wing-sailing. He became a regular air gymnast, running down the sides of an artificial mound until the wings lifted him up and enabled him to float a considerable distance before reaching earth again. His wings had an area of 160 square feet, or about a foot to every pound weight. He was killed by the wings collapsing in mid-air. A similar fate also overtook Mr. Percy Pilcher, who abandoned the initial run down a sloping surface in favour of being towed on a rope attached to a fast-moving vehicle. At present Mr. Octave Chanute, of Chicago, is the most distinguished member of the ”gliding” school. He employs, instead of wings, a species of kite made up of a number of small aerocurves placed one on the top of another a small distance apart.
These box kites are said to give a great lifting force for their weight.
These and many other experimenters have had the same object in view--to learn the laws of equilibrium in the air. Until these are fully understood the construction of large flying-machines must be regarded as somewhat premature. Man must walk before he can run, and balance himself before he can fly.
There is no falling off in the number of aerial machines and schemes brought from time to time into public notice. We may a.s.sure ourselves that if patient work and experiment can do it the problem of ”how to fly” is not very far from solution at the present moment.
As a sign of the times, the War Office, not usually very ready to take up a new idea, has interested itself in the airs.h.i.+p, and commissioned Dr. F. A. Barton to construct a dirigible balloon which combines the two systems of aerostation. Propulsion is effected by six sets of triple propellers, three on each side. Ascent is brought about partly by a balloon 180 feet long, containing 156,000 cubic feet of hydrogen, partly by nine aeroplanes having a total superficial area of nearly 2000 square feet. The utilisation of these aeroplanes obviates the necessity to throw out ballast to rise, or to let out gas for a descent. The airs.h.i.+p, being just heavier than air, is raised by the 135 horse-power motors pressing the aeroplanes against the air at the proper angle. In descent they act as parachutes.
The most original feature of this war balloon is the automatic water-balance. At each end of the ”deck” is a tank holding forty gallons of water. Two pumps circulate water through these tanks, the amount sent into a tank being regulated by a heavy pendulum which turns on the c.o.c.k leading to the end which may be highest in proportion as it turns off that leading to the lower end. The idea is very ingenious, and should work successfully when the time of trial comes.
Valuable money prizes will be competed for by aeronauts at the coming World's Fair at St. Louis in 1903. Sir Hiram Maxim has expressed an intention of spending 20,000 in further experiments and prizes. In this country, too, certain journals have offered large rewards to any aeronaut who shall make prescribed journeys in a given time. It has also been suggested that aeronautical research should be endowed by the state, since England has nothing to fear more than the flying machine and the submarine boat, each of which tends to rob her of the advantages of being an island by exposing her to unexpected and unseen attacks.
Tennyson, in a fine pa.s.sage in ”Locksley Hall,” turns a poetical eye towards the future. This is what he sees--
”For I dipt into the future, far as human eye could see, Saw the vision of the world and all the wonder that would be, Saw the heavens fill with commerce, argosies of magic sail, Pilots of the purple twilight dropping down with costly bales, Heard the heavens fill with shouting, then there rained a ghostly dew, From the nations' airy navies, grappling in the central blue.”
Expressed in more prosaic language, the flying-machine will primarily be used for military purposes. A country cannot spread a metal umbrella over itself to protect its towns from explosives dropped from the clouds.
Mail services will be revolutionised. The pleasure aerodrome will take the place of the yacht and motor-car, affording grand opportunities for the mountaineer and explorer (if the latter could find anything new to explore). Then there will also be a direct route to the North Pole over the top of those terrible icefields that have cost civilisation so many gallant lives. And possibly the ease of transit will bring the nations closer together, and produce good-fellows.h.i.+p and concord among them. It is pleasanter to regard the flying-machine of the future as a bringer of peace than as a novel means of spreading death and destruction.
TYPE-SETTING BY MACHINERY.
To the a.s.syrian brickmakers who, thousands of years ago, used blocks wherewith to impress on their unbaked bricks hieroglyphics and symbolical characters, must be attributed the first hesitating step towards that most marvellous and revolutionary of human discoveries--the art of printing. Not, however, till the early part of the fifteenth century did Gutenberg and Coster conceive the brilliant but simple idea of printing from separate types, which could be set in different orders and combinations to represent different ideas. For Englishmen, 1474 deserves to rank with 1815, as in that year a very Waterloo was won on English soil against the forces of ignorance and oppression, though the effects of the victory were not at once evident. Considering the stir made at the time by the appearance of Caxton's first book at Westminster, it seems strange that an invention of such importance as the printing-press should have been frowned upon by those in power, and so discouraged that for nearly two centuries printing remained an ill-used and unprogressive art, a giant half strangled in his cradle. Yet as soon as prejudice gave it an open field, improved methods followed close on one another's heels. To-day we have in the place of Caxton's rude hand-made press great cylinder machines capable of absorbing paper by the mile, and grinding out 20,000 impressions an hour as easily as a child can unwind a reel of cotton.
Side by side with the problem how to produce the greatest possible number of copies in a given time from one machine, has arisen another:--how to set up type with a proportionate rapidity. A press without type is as useless as a chaff-cutter without hay or straw. The type once a.s.sembled, as many casts or stereotypes can be made from it as there are machines to be worked. But to arrange a large body of type in a short time brings the printer face to face with the need of employing the expensive services of a small army of compositors--unless he can attain his end by some equally efficient and less costly means. For the last century a struggle has been in progress between the machine compositor and the human compositor, mechanical ingenuity against eye and brains. In the last five years the battle has turned most decidedly in favour of the machine. To-day there are in existence two wonderful contrivances which enable a man to set up type six times as fast as he could by hand from a box of type, with an ease that reminds one of the mythical machine for the conversion of live pigs into strings of sausages by an uninterrupted series of movements.
These machines are called respectively the Linotype and Monotype.
Roughly described, they are to the compositor what a typewriter is to a clerk--forming words in obedience to the depression of keys on a keyboard. But whereas the typewriter merely imprints a single character on paper, the linotype and monotype cast, deliver, and set up type from which an indefinite number of impressions can be taken.
They meet the compositor more than half-way, and simplify his labour while hugely increasing his productiveness.
As far back as 1842 periodicals were mechanically composed by a machine which is now practically forgotten. Since that time hundreds of other inventions have been patented, and some scores of different machines tried, though with small success in most cases; as it was found that quality of composition was sacrificed to quant.i.ty, and that what at first appeared a short cut to the printing-press was after all the longest way round, when corrections had all been attended to. A really economical type-setter must be accurate as well as prolific.
Slipshod work will not pay in the long run.
Such a machine was perfected a few years ago by Ottmar Mergenthaler of Baltimore, who devised the plan of casting a whole _line of type_. The Linotype Composing Machine, to give it its full t.i.tle, produces type all ready for the presses in ”slugs” or lines--hence the name, Lin' o'
type. It deserves at least a short description.
The Linotype occupies about six square feet of floor s.p.a.ce, weighs one ton, and is entirely operated by one man. Its most prominent features are a sloping magazine at the top to hold the bra.s.s matrices, or dies from which the type is cast, a keyboard controlling the machinery to drop and collect the dies, and a long lever which restores the dies to the magazine when done with.
[Ill.u.s.tration: _By kind permission of The Linotype Co._
_The Linotype Machine. By pressing keys on the key-board the operator causes lines of type to be set up, cast, and arranged on the ”galley”
ready for the printers._]
The operator sits facing the keyboard, in which are ninety keys, variously coloured to distinguish the different kinds of letters. His hands twinkle over the keys, and the bra.s.s dies fly into place. When a key is depressed a die shoots from the magazine on to a travelling belt and is whirled off to the a.s.sembling-box. Each die is a flat, oblong bra.s.s plate, of a thickness varying with the letter, having a large V-shaped notch in the top, and the letter cut half-way down on one of the longer sides. A corresponding letter is stamped on the side nearest to the operator so that he may see what he is doing and make needful corrections.
As soon as a word is complete, he touches the ”s.p.a.cing” lever at the side of the keyboard. The action causes a ”s.p.a.ce” to be placed against the last die to separate it from the following word. The operations are repeated until the tinkle of a bell warns him that, though there may be room for one or two more letters, the line will not admit another whole syllable. The line must therefore be ”justified,” that is, the s.p.a.ces between the words increased till the vacant room is filled in. In hand composition this takes a considerable time, and is irksome; but at the linotype the operator merely twists a handle and the wedge-shaped ”s.p.a.ces,” placed thin end upwards, are driven up simultaneously, giving the lateral expansion required to make the line of the right measure.