The prin ciple of the modern automatic sight is made clear in figs.
The essential change from the link and pin to the automatic coupler is in the outboard end or head of the draw-bar.
The Murray automatic system was designed specially for dealing with heavy traffic on long lines.
Voters are registered biennially, and every five years there is an automatic redistribution of seats on a voters' basis.
Normally a switch attached to the key cuts the battery off, and connects the line direct through the receiving relay; this switch is turned to " send " when transmission commences, and is moved back to " receive " when it ceases: this movement is done quite mechanically by the telegraphist, and as it is practically never forgotten, automatic devices (which have often been suggested) to effect the turning are wholly unnecessary.
- Automatic Coupling for Freight Cars (U.S.A.).
The improvements in gun mountings mentioned above led the way to the introduction of the automatic sight.
It was found impossible to make the Morse ink writer so sensitive that it could record signals sent over land lines of several hundred miles in length, if the speed of transmission was very much faster than that which could be effected by hand, and this led to the adoption of automatic methods of transmission.
This received perforated tape is then used to control what is known as the printer or automatic typewriter, a machine that translates the tape perforations into letters and prints the messages in Roman type in page form.
But it is still more curious that it was not afterwards carried out, for the communication of automatic symmetrical motion to both segments only involves a simple alteration previously described.
An automatic sight is a sight connected in such a manner with the elevating gear of the gun, that when the sight is directed on the water-line of a target at any range the gun will ---- have the proper quadrant g B elevation for that range.
In the Wheatstone automatic apparatus three levers are placed side by side, each acting on a set of small punches and on mechanism for feeding the paper forward a step after each operation of the levers.
The messages in the form of perforated tape are then passed through an automatic transmitter, something like a Wheatstone transmitter, at a speed of about 100 words a minute.
The Murray automatic system is not regarded as suitable for short telegraph lines or moderate traffic, printing telegraphs on the multiplex principle being considered preferable in such circumstances.
The automatic curb sender was originally designed by Lord Kelvin for the purpose of diminishing the effect of inductive re- Au tardation in long cables.
With the adoption of relays the signalling between the subscribers and the exchange became automatic, and, with the introduction of the principle of double and automatic supervision on the cord circuits, it became possible for the operators to tell at any instant the state of a connexion.
The use of automatic couplers for freight cars throughout the United States, introduced in 1893-1900, greatly reduced the number of deaths and injuries in coupling, and the use of air brakes on freight cars, now universal, has reduced the risk to the men by making it less necessary for them to ride on the roofs of high box-cars, while at the same time it has made it possible to run long trains with fewer men; but except in these two features the freight service in America continues to be a dangerous occupation.
Another form of coupler, which used to be universal in the United States, though it has now been almost entirely superseded by the automatic coupler, was the " link and pin," which differed fundamentally from the couplers commonly used in Europe, in the fact that it was a buffer as well as a coupler, no :side buffers being fitted.
To make this apparatus more perfectly automatic, an arrangement for continually adding to and mixing with the juice the proper proportion of milk of lime has been adapted to it; and although it may be objected that once the proportion has been determined no allowance is made for the variation in the quality of the juice coming from the mill owing to the variations that may occur in the canes fed into the mills, it is obviously as easy to vary the proportion with the automatic arrangement from time to time as it is to vary in each separate direction, if the man in charge will take the trouble to do so, which he very seldom does with the ordinary defecators, satisfying himself with testing the juice once or twice in a watch.
Owing to the difficulty of maintaining perfect balance on duplexed cables, curb sending is not now used, but the signals are transmitted by means of an apparatus similar to the Wheatstone automatic transmitter used on land lines and differing from the latter only in regard to the alphabet employed; the signals from the transmitter actuate a relay having heavy armatures which in turn transmit the signals to the cable; this arrangement gives very firm signals, a point of great importance for good working.
By a modification of this apparatus the message, instead of being immediately re-transmitted into the second cable, can be punched on a paper slip, which can be inserted in the usual way into an automatic transmitter, so as to send either cable or Morse signals.
The engines were built on the Worsdell and Von Borries plan, and were fitted with an ingenious startingvalve of an automatic character to overcome the difficulties of starting.
This arrangement is only partly automatic, since it often happens that when two cars are brought together to couple the knuckles are closed and must be opened by hand.
At that time a member of the Association referred to the disappearance of automatic couplers which had been introduced thirty or forty years before.
This body pursued the subject with more or less diligence, and in 1884 laid down the principle that the automatic coupler should be one acting in a vertical plane - that is, the engaging faces should be free to move up and down within a considerable range, in order to provide for the differences in the height of cars.
Automatic couplers resembling the Janney are adopted in a few special cases in Great Britain and other European countries, FIG.
The Chaff-cutting Machines (Accidents) Act 1897 is a measure very similar in its intention to the Threshing Machines Act 1878, and provides for the automatic prevention of accidents to persons in charge of chaff-cutting machines.
An automatic sight based on the Italian sight was tried in 1878-1879.
In 1882 Jenkin invented an automatic method of electric transport for goods - "telpherage" - but the completion of its details was prevented by his death on the 12th of June 1885.
The first method is in general use for steam cranes; it allows for a far greater range of power in the brake, but is not automatic, as is the second.
A long-standing cause of complaint on the part of the public has been the common refusal of cab-drivers to accept their legal fares, but, on the other hand, several attempts to introduce cabs with an automatic taximeter failed, until the introduction of motor cabs, of which a few had already been plying for some time when in 1907 a large number, provided with taximeters, were put into service.
These latter pass to automatic weighing machines, which drop them, in quantities of 1 cwt., into wooden boxes of uniform measurement, made to contain that weight; and the boxes are then conveyed to the storehouse, ready for sale.
Thus the simple connexion of the two screws by cogwheels to give them automatic opposite motion is not an available method unless the separation of the segments is independently measured by scales.
When cordite replaced black powder, and the gun sights and all in front of the gun were no longer obscured by hanging clouds of smoke, it became a desideratum, and, as the automatic sight, it was reintroduced by Sir G.
21 and 22, which show a combined rocking-bar and automatic sight.
The heavier cores, with the consequent advance in speed of working attainable, have necessitated the introduction of automatic sending, the instruments adopted being in general a modification of the Wheatstone transmitter adapted to the form of cable signals, while the regularity of transmission thus secured has caused its introduction even on circuits where the speed cannot exceed that of the ordinary operator's hand signalling.
This form of automatic coupler has now gained practically universal acceptance in the United States.
The investigation of Carpenter on unconscious cerebration and of Faraday on unconscious muscular action showed early in the movement that it was not necessary to look outside the medium's own personality for the explanation of even intelligent communications unconsciously conveyed through table-tilting, automatic writing and trance-speaking - provided the matter communicated was not beyond the range of the medium's own knowledge or powers.
The automatic inlet of cold water to the hot water system from the main house tank or other source is controlled by a ball valve, which is so fixed as to allow the water to rise no more than an inch above the bottom of the tank, thus leaving the remainder of the space clear for expansion.
At the receiving end are a similar antenna and resonant circuit, and a telephone is connected across one part of the latter through an automatic interrupting device called by Poulsen a " ticker."
The idea of automatic telephony is to substitute for the operator of the manual exchange an electromechanical or other switching system, which, controlled in its movement by the action of the subscriber, will automatically select, connect and disconnect circuits as desired.
In certain respects, on the other hand, America has gone further than the United Kingdom, especially in the matter of automatic signalling, and in the operating of points and signals by electrical power or air-pressure instead of manual labour.
The common form of non-automatic coupler, used in Great Britain for goods wagons, consists of a chain and hook; the chain hangs loosely from a slot in the draw-bar, which terminates in a hook, and coupling is effected by slipping the =chain of one vehicle over the hook of the next.
Obtained from various persons automatic script affording important new material for investigation and which prima facie supports the spiritualistic hypothesis.
In America, also, freight trains are fitted with an automatic continuous brake, whereas in the United Kingdom this appliance is required by law only in the case of passenger trains, and in fact is not fitted to goods and mineral trains except in a few isolated instances.
- Theory of the Automatic Sight.
The principle of combined sight and range-finder had long been known, Automatic and was embodied in the so-called " Italian " sight, but, sights.
Cigarettes were entirely prepared by the smoker himself; Ci but now they are very largely made by automatic machinery.