2021-04-14 12:19:59

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ENGLISH In Lige things were no longer so depressing as at the time of my first visit. There was some traffic in the streets, and by order of the German authorities the shops had been reopened.Steam and other machinery applied to the transport of material and travel, in navigation and by railways, comprises the greater share of what may be called engineering products; and when we consider that this vast interest of steam transport is less than a century old, and estimate its present and possible future influence on human affairs, we may realise the relation that mechanical science bears to modern civilisation.

Between my tours through the Lige district I made a trip in the direction of Tongres, because I wanted to know what had become of all those Germans who had crossed the Meuse near Lixhe. It was remarkable to notice how friendly the Flemings of that district behaved with regard to the Germans. Although they criticised the violation of the country's neutrality sharply, and every family was proud of the sons who had taken up arms in defence of their Fatherland, yet they judged quite kindly the German soldiers who passed through their district. I often heard expressions full of pity toward those men, who could not help themselves, but were compelled to do whatever their superiors commanded them.

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The valve gearing of automatic steam-hammers to fill the two conditions of allowing a dead or an elastic blow, furnishes one of the most interesting examples of mechanical combination.Ink used in drawing should always be the best that can be procured; without good ink a draughtsman is continually annoyed by an imperfect working of pens, and the washing of the lines if there is shading to be done. The quality of ink can only be determined by experiment; the perfume that it contains, or tinfoil wrappers and Chinese labels, are no indication of quality; not even the price, unless it be with some first-class house. To prepare ink, I can recommend no better plan of learning than to ask some one who understands the matter. It is better to waste a little time in preparing it slowly than to be at a continual trouble with pens, which will occur if the ink is ground too rapidly or on a rough surface. To test ink, a few lines can be drawn on the margin of a sheet, noting the shade, how the ink flows from the pen, and whether the lines are sharp; after the lines have dried, cross them with a wet brush; if they wash readily, the ink is too soft; if they resist the water for a time, and then wash tardily, the ink is good. It cannot be expected that inks soluble in water can permanently resist its action after drying; [83] in fact, it is not desirable that drawing inks should do so, for in shading, outlines should be blended into the tints where the latter are deep, and this can only be effected by washing.

"Devant-le-Pont?"2. Drawings in true elevation or in section are based upon flat planes, and give dimensions parallel to the planes in which the views are taken.

The latter seems a plausible theory, and perhaps a correct one; but there are two facts in connection with the operation of reaction water-wheels which seem to controvert the latter and favour the first theory, namely, that reaction wheels in actual practice seldom utilise more than forty per cent. of useful effect from the water, and that their speed may exceed the initial velocity of the water. With this the subject is left as one for argument or investigation on the part of the reader.To attain a double effect, and avoid the loss pointed out, Mr Ramsbottom designed what may be called compound hammers, consisting of two independent heads or rams moving in opposite directions, and acting simultaneously upon pieces held between them.

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It was a fantastic night. Trains arrived out of the foggy darkness, their screeching whistle resounding from the far distance, and when they steamed into the station a storm of noise arose. All these trains brought British prisoners of war, captured by the Germans at St. Quentin, and hundreds of German soldiers escorted the trains, which were all covered over with green branches, and looked like copse-wood sliding along the railroad. As soon as they rumbled into the station the escorts sang loudly their patriotic songs, and "Germany before all other!" ("Deutschland über Alles!") vibrated through the fog.

A pair of spring calipers will illustrate this principle. The points are always steady, because the spring acting continually in one direction compensates the loose play that may be in the screw. In a train of tooth wheels there is always more or less play between the teeth; and unless the wheels always revolve in one direction, and have some constant resistance offered to their motion, 'backlash' or irregular movement will take place; but if there is some constant and uniform resistance such as a spring would impart, a train of wheels will transmit the slightest motion throughout.Tempering may be called a mystery of the smith-shop; this operation has that attraction which characterises every process that is mysterious, especially such as are connected with, or belong to mechanical manipulation. A strange and perhaps fortunate habit of the mind is to be greatly interested in what is not well understood, and to disregard what is capable of plain demonstration.

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Apr-14 12:19:59