Gleissner, to whom I communicated my new invention, offering him, at the same time, my services for the publication of his music. The specimens of music, and other printing, which I showed him, obtained his and his wife's highest approbation; he admired the neatness and beauty of the impressions, and the great expedition of the printing; and, feeling himself flattered by my confidence, and the preference I gave him, he immediately proposed to undertake the publication of his music on our joint account.
I had, in the mean time, procured a common copper-plate printing press, with two cylinders; and, though it was very imperfect, it still enabled me to take neat impressions from the stone plates. Having, therefore, copied the twelve songs, composed by Gleissner, with all possible expedition, on stone, I succeeded in taking, with the assitance of one printer, copies from it. The composiing, writing on stone, and printing, and had been accomplished in less than a fortnight; and in a short time we sold of these songs to the amount of florins, though the whole expense of stones, paper, and printing, did not exceed 30 florins, which left us a clear profit of 70 florins.
As Senefelder recounts in his Complete Course of Lithography p. This was drawn on stone by Senefelder and printed at Mr. Falter's house by two soldiers whom Senefelder had instructed in the process of printing. Falter at last prefered printing again from copper.
On June 20, Senefelder received British patent no. It may be worthy of note that, as the specification of the patent indicated, Senefelder foresaw the wide range of applications of his process beyond strictly printing on paper. By Senefelder adapted zinc plates as substitutes for limestone in the process of lithography. Zinc plates eliminated the necessity of using smooth fine-grained limestone, and made it possible to lithograph larger images with zinc plates that were much lighter in weight, and thus more manageable in the press than stones of equivalent dimensions.
Like all rulers of his age, Maximilian was acutely aware of his personal status; he became the first ruler to recognize the potential of the print as an effective way of perpetuating his name and dynasty. It eventually became the first country to officially adopt the system for normal use.
Napoleon Bonaparte introduced a modified system in , though this would not go on to become the standard. But because Napoleon was so influential at this time and had claimed so many lands in the name of France, use of this modified system spread even to foreign lands which helped it to become the most widely used system of measurement today.
See the Tool. See the Collection. This has been possible since the 2nd century BC by means of the astrolabe. From the beginning of the European voyages in the 15th century practical improvements have been made to the astrolabe - mainly by providing more convenient calibrated arcs on which the user can read the number of degrees of the sun or a star above the horizon.
The size of these arcs is defined in relation to the full circle. The use of such arcs in conjunction with the traditional astrolabe is evident from a text of about voyaging to the West Indies. The author talks of 'quadrant and astrolabe, instruments of astronomy'.
The important development during the 18th century is the application of optical devices mirrors and lenses to the task of working out angles above the horizon. Slightly differing solutions, by instrument makers in Europe and America, compete during the early decades of the century.
The one which prevails - largely because it is more convenient at sea - is designed as an octant in by John Hadley, an established English maker of reflecting telescopes.
Hadley's instrument, like others designed by his contemporary rivals, uses mirrors to bring any two points into alignment in the observer's sight-line. For the navigator these two points will usually be the sun and the horizon. To read the angle of the sun, the observer looks through the octant's eyepiece at the horizon and then turns an adjusting knob until the reflected orb of the sun through a darkened glass is brought down to the same level.
In Hadley adds an improvement which becomes standard, installing a spirit level so that the horizontal can be found even if the horizon is not visible. With this Hadley's octant becomes a sextant, and the instrument in use ever since finds its essential form. The researches of William Gilbert , at the start of the 17th century, lead eventually to simple machines with which enthusiasts can generate an electric charge by means of friction.
The current generated will give a stimulating frisson to a lady's hand, or can be discharged as a spark. In an amateur scientist, Ewald Georg von Kleist, dean of the cathedral in Kamien, makes an interesting discovery.
After partly filling a glass jar with water, and pushing a metal rod through a cork stopper until it reaches the water, he attaches the end of the nail to his friction machine. After a suitable amount of whirring, the friction machine is disconnected.
When Kleist touches the top of the nail he can feel a slight shock, proving that static electricity has remained in the jar. It is the first time that electricity has been stored in this way, for future discharge, in the type of device known as a capacitor. In the same principle is discovered by Pieter van Musschenbroek, a physicist in the university of Leyden. As a professional, he makes much use of the new device in laboratory experiments.
Though sometimes called a Kleistian jar, it becomes more commonly known as the Leyden jar. James Watt and the condenser: In a model of a Newcomen steam engine is brought for repair to the young James Watt, who is responsible for looking after the instruments in the physics department of the university of Glasgow.
In restoring it to working order, he is astonished at how much steam it uses and wastes. The reason, he realizes, is that the machine's single cylinder is required to perform two opposing functions. It must receive the incoming steam at maximum pressure to force the piston up for which it needs to be as hot as possible , and it must then condense the steam to form a vacuum to pull the cylinder down for which it needs to be as cool as possible.
The solution occurs to Watt when he is walking near Glasgow one Sunday in May The two functions could be separated by providing a chamber, outside the cylinder but connecting with it, in which a jet of cold water will condense the steam and cause the vacuum. This chamber is the condenser, for which Watt registers a patent in The principle has remained an essential part of all subsequent steam engines. It is the first of three major improvements which Watt makes in the basic design of steam-driven machinery.
The other two are the double-acting engine and the governor , developed in the s. Machine tools, gun barrels and cylinders: John Wilkinson, an ironmaster in Staffordshire and Shropshire, has been building up a lucrative arms trade. In he invents a machine, powered by a water wheel, which can drill with unprecedented accuracy through the length of a cast-iron cylinder to create the barrel of a cannon. It is a turning point in the development of machine tools. James Watt realizes that Wilkinson's new machine is capable of the precision required for an efficient steam-engine cylinder.
In Wilkinson delivers to Birmingham the first of the thousands of cylinders he will bore for the firm of Boulton and Watt. Boulton finds them 'almost without error; that of 50 inches diameter doth not err the thickness of an old shilling' in any part.
Double-acting engine and governor: Just as James Watt applied a rational approach to improve the efficiency of the steam engine with the condenser , so now he takes a logical step forward in a modification patented in His new improvement is the double-acting engine.
Watt observes that the steam is idle for half of each cycle. During the downward stroke, when the vacuum is exerting atmospheric force on the piston, the valve between boiler and cylinder is closed. Watt takes the simple step of diverting the steam during this part of the cycle to the upper part of the cylinder, where it joins with the atmospheric pressure in forcing the cylinder down - and thus doubles its effective action.
The most elegant contraption devised by Watt is in use from It is the governor - the first example of the type of controlling device required in industrial automation, and a feature of all steam engines since Watt's time. Watt's governor consists of two arms, hinged on a central pivot and rotated by the action of the steam engine. Each arm has a heavy ball at the end.
As the speed increases, centrifugal force moves the balls and the arms outwards. This action narrows the aperture of a valve controlling the flow of steam to the engine. As the power is slowly cut off, the speed of the engine reduces and the balls subside nearer to the central column - thus slightly opening the valve again in a permanent process of adjustment.
Although hydrogen has been isolated by Cavendish in the s, and shown to be fourteen times lighter than air, it is not until the early s that Europe's inventors are suddenly gripped with a feverish interest in using the concept to achieve a form of flight. In scientists in both England and Switzerland fill soap bubbles with hydrogen and see them rise rapidly to the ceiling, but similar experiments with animal bladders prove disappointing. In the event a more elementary idea, requiring none of the achievements of recent researches, provides the breakthrough.
In November a French manufacturer of paper, Joseph Montgolfier, wonders whether the simple fact of smoke rising might not be used to carry a balloon aloft. With his brother Etienne he begins making experiments.
By June they are sufficiently confident to give a public demonstration in the town of Annonay. They light a bonfire of straw and wool under a canvas and paper balloon with a diameter of about 35 feet. An astonished crowd sees the apparatus inflate and then drift into the sky. It rises, they estimate, to more than feet, stays in the air for ten minutes, and descends gently to earth yards away.
A report is immediately sent by the representatives of the local assembly to the Academy of Sciences in Paris. The news causes a sensation. The Montgolfiers are invited to the capital to demonstrate their invention. Etienne makes the journey on their joint behalf and constructs a balloon to be launched at Versailles on September 19 in the presence of Louis XVI.
This time the flying globe or aerostatic sphere both are contemporary phrases carries living passengers - a sheep, a cock and a duck. The trio travel more than two miles and land unharmed, except that the cock has been kicked by the sheep. The king, watching it all through his telescope, raises the Montgolfier family into the ranks of the nobility. The final Montgolfier triumph takes place in November.
A larger balloon is constructed, 46 feet in diameter, with a metal container to hold the burning straw hanging on chains just inside it. A basket, suspended below, is large enough to carry two people. Rigorous tests take place in a Paris garden. At last, on November 21, all is considered ready. Four hands will be needed to stoke the fire with bundles of straw. An excited crowd attempts to follow the path of the balloon as it rises and drifts away across Paris.
In spite of alarming moments such as their basket catching fire , the aeronauts make a successful flight, travelling about six miles in twenty-five minutes.
They land safely, narrowly missing a windmill. Those who have followed on horses are immediately on the scene. History has its first aviators. Year of the balloon - hydrogen:
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