86 



POPULAE SCIENCE NEWS. 



[June, 1889 



of balance and hair-spring, and any disturbing 

 cause affecting the elasticity of this spring, or alter- 

 ing the moment of inertia of the balance, pro- 

 duces its corresponding change in the rate. 



Thus the eifect of temperature on a watch not 

 compensated is very marked. An increase of 62° 

 F. has caused a loss of 393 seconds in 24 hours; 62 

 seconds of this loss being due to expansion of the 

 diameter of the balance, the lessened elasticity of 

 the spring resulting in a loss of 312 seconds, while 

 a further loss of 19 seconds was due to increased 

 length of the spring through expansion. 



To obviate this, the balance is usually compen- 

 sated bv being constructed of two metals, brass and 

 steel, which, by their unequal coefficients of expan- 

 sion, change the moment of inertia of the balance, 

 so as to counteract these deficiencies. It is clear, 

 then, that any condition which otherwise alters the 

 elastic power of the spring, or any force having a 

 varying influence on the balance, must ultimately 

 affect the time-keeping qualities of the watch. Mag- 

 netic influence is such a disturbing cause; it may- 

 produce a slowing or increasing of the rate, and it 

 may even stop the watch. 



If a watch has been exposed in a magnetic field, 

 the balance-spring may become so magnetized as to 

 exhibit a tendency to stick when coiled, giving rise 

 to a change of rate, such as would be produced by a 

 variation in the elasticity of the spring. In addi- 

 tion, the escape wheel and fork may attract each 

 other strongly, and the balance, in turn, with these 

 parts, may be attracted by the magnetism in the 

 main-spring and various steel screws. It not 

 infrequently happens that these forces become so 

 adjusted that they stop the balance on a "dead cen- 

 tre." The magnetism of most of these parts, how- 

 ever, acts as a constant factor, and produces merely 

 stoppage. 



With the magnetised balance, the case is different. 

 It revolves in a field of constantly changing polar- 

 ity, due to the motion of the steel escape wheel and 

 the main-spring. The first would occasion a throb- 

 bing rate, and scarcely be noticeable in the long 

 run ; the second would alter the rate irregularly, at 

 times accelerating and at others retarding the bal- 

 ance. These would not necessarily compensate 

 each other, and would spoil the time-keeping quali- 

 ties of the movement. 



The chances of exposure to magnetic influence are 

 numerous and constantly multiplying, owing to the 

 increasing use of electricity. The electric propul- 

 sion of street cars is one thing that may work havoc 

 with ordinary watches, and, as its employment is 

 spreading so rapidly, will doubtless cause a general 

 demand for a non-magnetic watch. Of course there 

 is now a felt need for this amongst electricians gen- 

 erally, and those employed in running dynamos and 

 motors. All the stationary iron and steel about a 

 railroad, as well as the cars and locomotives, is apt 

 to be more or less magnetized. Employes who 

 travel over the same route find their watches occa- 

 sionally becoming unreliable. Some companies 

 have recognized this, and adopted preventive meas- 

 ures. 



When once a watch has become magnetized, it 

 can usually be taken out without harm. One 

 method that has given satisfactory results is to 

 twirl the watch rapidly in a strong field of constant 

 polarity ; another, is to place it in a helix, through 

 which an alternating current is passing. 



There are now two methods employed for render- 

 ing a watch non-magnetic. One uses a shield or 

 case of iron, but the results obtained with these are 

 conflicting. Some investigators find them insuffi- 

 cient in strong fields, though they may afford suffi- 

 cient protection against weak ones. They seem to 



be in favor with railroad companies, some of which 

 make their use compulsory. 



The other aims to make the watch non-magnetic 

 in its construction, producing a time-piece which is 

 thoroughly reliable under all conditions of service. 

 For the balance, brass would be sufficiently non- 

 magnetic for ordinary purposes, but, in order to 

 have compensation, there must be some metal sub- 

 stituted for the steel. In oije make of these watches, 

 the balance and hair-spring are made of alloys of 

 palladium, the rim of the balance consisting of two 

 alloys, having different rates of expansion, making 

 a thoroughly compensated and non-magnetic bal- 

 ance. The escapement is of aluminum-bronze, so 

 that the watch is not liable to be stopped by mag- 

 netism. Another leading make of non-magnetic 

 watches employs alloys of platinum for both the 

 balance and escapement. The non-magnetic quali- 

 ties of these alloys is derived from combination of 

 certain metals in such proportions that their mag 

 netic qualities exactly neutralize each other. Plati 

 num and palladium resemble iron in their magnetic 

 behavior, — that is, a strong magnet .so affects them 

 that they exhibit polarity in the same order as the 

 inducing magnet. With copper, gold, and silver, 

 the reverse is the case. The former are termed 

 paramagnetic; the latter diamagnetic. The metals 

 actually entering into the alloy of the balance and 

 spring of one make of watch are, palladium, plati- 

 num, nickel, and steel — paramagnetic; silver, cop- 

 per, and gold — diamagnetic. This alloj* is capable 

 of being tempered to a high degree, and is said to 

 possess an elasticity superior to steel. 



Though the introduction of the non-magnetic 

 watch is comparatively recent, yet, as they seem to 

 be correct in principle, and their worth undoubtedly 

 proven by rigid tests, they are entitled to be re- 

 garded as marking a great advance in horology. 

 This is especially true, if the claims of an American 

 company are well founded, that their platinum alloy 

 is superior to steel for use in the hair-spring, since 

 its elasticity is not the result of hammering, rolling, 

 or tempering, but is a property of the metal itself 

 They state that the spring may be heated red-hot, 

 and be as elastic as before, when brought to its 

 original temperature. Thus the attempt to render a 

 watch non-magnetic has resulted, independently of 

 this quality, in producing movements superior to 

 those already brought to such a high state of per- 

 fection. 

 Ohio University, Athens, O. 



INDUSTRIAL MEMORANDA. 



Hollow Ingots. — In Sweden, hollow steel ingots 

 are made by casting steel in molds hung on trun- 

 nions, allowing the sides to chill to the required 

 thickness and pouring out the still liquid in the 

 centre. These hollow ingots go to England, where 

 they are drawn out cold into tubing. 



Glass Bottles. — The Heye factory for glass 

 bottles at Gerresheim, near Dusseldorf, produces on 

 an average 200,000 a day, and, if necessary, can 

 turn out 300,000. From 1,800 to 3,000 men and 

 women are regularly employed in the works, and 

 find accommodation in the adjoining model town. 



Automatic Candles. — A new candle has been 

 brought out, which extinguishes itself in an hour. 

 This it does by means of a tiny extinguisher of tin, 

 which is fastened in the wax by wires, and which 

 effectually performs its task. It is only necessary to 

 remove this diminutive extinguisher when its work 

 is done, and the candle is again ready to burn 

 another hour. 



Highest Water-Power Head. — I'rance claims 

 the honor of utilizing a higher water pressure than 

 that recently put in operation in the Chollar shaft 

 on the Comstock lode, in Nevada. At Brignoud, 



one and one-quarter miles from the valley of 

 Gresivaudad, near Grenoble, a turbine 9 feet, 10 

 inches in diameter was put in operation in the year 

 1875, utilizing a head of 1,638 feet. It is still work- 

 ing, and gives a force of 1,500 horse-power, with a 

 flow of 75 gallons of water per second. 



Chinese Railroads. — In the summer of 18S8. 

 the railway between Lutai and Taku, in China, a 

 distance of 60 miles, was opened, and in the autumn 

 the section between Taku and Tientsin was com- 

 pleted. The passenger traffic on this line is said to 

 be very active, although the trains only run at pres- 

 ent at the rate of 20 miles an hour, as they also 

 serve for the transport of goods. It is expected that 

 the railway will be opened as far as Pekin some 

 time during the present year, when the Chinese 

 capital will be reached from Tientsin in about ontf 

 hour and a half. Two short lines are also being 

 constructed in the island of Formosa, one of whicli 

 runs from Kelung through the Tamsui valley. 



Electric Watches and Clocks. — M. L. Hus- 

 sey, of Menio Park, N. J., has secured a patent for :i 

 watch to run by electricity. Mr. Husse^' has been 

 II years at work on his inventions, and has secured 

 patents on 13 appliances necessary in the manufiic- 

 ture of his clocks and watches. There are four of 

 these, including a marine clock. The peculiarity 

 about them is the gravity movement, which, aided 

 by a small electric current, moves the pendulums of 

 the clocks and the large balance wheels of tin 

 watches. The battery is enclosed in the watch-case 

 and with it the lime-piece will run for a whole ve.t} 

 without any attention. In time it is expected thai 

 five-year watches and clocks can be manufactured. 

 The new watches and clocks contain only one-thini 

 as many parts as the ordinary iftstrument. 



The Working Force of the Pennsylv.\nia 

 Railroad. — President Roberts has made the usual 

 semi-annual muster of the employes of the Pennsvl- 

 vania Railroad Company, and finds that he h:i> 

 nearly 90,000 men and boys on the rolls. Thi- 

 exact number, including the president himself, is 

 89,369. These employes manage and operate 7,581 

 miles of railway. The employes are unevenly dis 

 tributed over the company's .system. On the 1,817 

 miles of road from Pittsburg to New York, 45.2^7 

 men find employment. On the 2,396 miles of leased, 

 operated, and controlled lines east of Pittsburg aiul 

 Erie, the employes number 11,689. There are 56,- 

 916 men employed on the 4.213 miles of road east of 

 Pittsburg and Erie. The employes on the liiu-, 

 west of Pittsburg and Erie number 32,453. Tiii- 

 completes the total of S9.369 men. The thousands 

 working in forests, shops, and mills, where the com- 

 pany's supplies are turned out, are not included in 

 this total. 



The Largest Cotton Mh.l. — It is notgenerall\ 

 known, but it appears that the largest cotton mill in 

 the world is that of Krahnholm, in Russia. In this 

 immense establishment there are 340,000 spindUs 

 and 2,200 looms, giving employment to some 7.(»«i 

 hands. The motive power, to the extent of 6,3(0 

 horse-power, is derived from a fall on the riM 1 

 Marowa, which actuates eight turbines, which wen 

 constructed in Augsburg. Four of these turbiius 

 develop 1,000 horse-power each, requiring the im- 

 mense volume of 4,000 gallons of water per second 

 One of these turbines was erected in 1867, and has 

 worked ever since, day and night, without any it- 

 pairs. The shafting exceeds 20,917 feet in lengtli. 

 The work-people are Russians and Esthanians, tin 

 latter, it is stated, being especially faithful and lal>i> 

 rious. The week's work is calculated at 79 hoius, 

 and the wages vary from $90 to .$30 per month 

 The heads of the various departments are moslI\ 

 Englishmen, the technical management of the con- 

 cern being almost entirely in their hands. 



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