Eye Glass
Eye glasses for watchmaker's use are mounted in many different styles. Some have horn, others have vulcanite and still others cork mountings. The vulcanite mounted glass with a light spring attached to sustain it in place is very popular with apprentices. The Clark patent glass, shown in Fig. 129, is becoming very popular in this country. It is provided with an annular reflector, with a central opening and corrugations, and so seated in the outer end of the glass as to reflect the rays of light falling on the outside of it in front of the glass, and concentrating them upon the object being viewed. It is especially useful in examining the inside of watches, as it often occurs that it is difficult to get light sufficient to do so. FACIO, NICHOLAS. A native of Geneva, who discovered the art of piercing holes in rubies, garnets and other stones. He first went to Paris and from there, in 1700, went to London, and there with the brothers Peter and Jacob de Beaufre carried on the business of watch jewelling. A patent on his process of piercing jewels was granted to him in England in May, 1704. FERGUSON, JAMES. A celebrated astronomer and mechanician. He was born in the year 1710, a few miles from Keith, a little village in Banffshire, in the north of Scotland. Ferguson can hardly be classed among horologists, although he made many improvements in the clocks of his day and many inventions in this line. In the year 1750 Ferguson invented and made his celebrated machine, known as the "Mechanical Paradox." This curious machine was made for the purpose of silencing a London watchmaker who did not believe in the doctrine of the Trinity. The paradox, which is illustrated in Fig. 131, is described by Ferguson as follows: "A is called the immovable plate, because it lies on a table whilst the machine is at work; B C is a moveable frame to be turned round an upright axis a (fixt in the centre of the immovable plate) by taking hold of the nob u. On the said axis is fixt the immoveable wheel D whose teeth take into the teeth of the thick moveable wheel E, and turns it round its own axis as the frame is turned round the fixt axis of the immoveable wheel D and in the same direction that the frame is moved. The teeth of the thick wheel E take equally deep into the teeth of the three wheels, F, G and H, but operate on these wheels in such a manner, that whilst the frame is turned round, the wheel H turns the same way that the wheel E does, the wheel G turns the contrary way, and the wheel F no way at all." Fig. 132 illustrates what Ferguson termed "a one-wheeled clock." The drawing he made in 1774 and there was no description accompanying it, simply these few words: "The number of wheels in a clock reduced to one, by means of a double 'scapement." This is a problem for the ingenious watch or clock maker to solve. James Ferguson died Nov. 16, 1776.