One of the many large Adders at Longchamps

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This page contains a photograph which is one of several belonging to the photo gallery pages which are part of several pages relating to the invention of the world's first automatic totalizator in 1913 and Automatic Totalisators, the company founded to develop, manufacture and export these systems.


There is one adder per runner in a race as well as a grand total adder. This is repeated for each pool that the system supported, in this case GAGNANT and PLACE translated from French, Win and Place. Some of these adders are visible in the first photograph in the Longchamps section of the photo gallery

An example of Storage memory before Electronics

This image shows one of the many Longchamps central processing system adders. Longchamps had 273 distributed Ticket Issuing Machines (TIMs). Impulses from the TIMs activated solenoids in the adder which tripped escapement wheels and the rotation of these wheels was summed to determine the investment on a particular runner. The adder in this image adds the investments on runner number 5 as indicated by the number on the adder. As the scanners in the following photo in the photo gallery, multiplexed seven TIMs onto a particular solenoid in the adders, these adders required 39 escapements to support the 273 TIMs. The rotation of each escapement wheel is summed by an epicyclic gear train. there are seven tubular sections visible in the middle of the adder spanning from the front of the adder to the rear. At the rear end of these tubes are the solenoids, escapement wheels and epicyclic gear trains. The rear of a couple of the adders are visible in the first image in the Longchamps photo gallery section showing the machine room. The tubes mentioned above are called Storage Screws. These remember the value of summed transactions recorded as rotation, of the fast adding shafts at the rear of the adder and are read by the slower to respond, inertia imposed acceleration limited, parts of the system at the front of the adder, as they catch up. An image of a partially assembled Longchamps adder from the rear, showing the adding shafts and storage screws, is at the end of the Longchamps section of the Photo Gallery.

Following is a description describing one of the nine storage screws running from the front to the back of the adder. Only seven are visible from this perspective however another two are hidden by the lower counter wheel display panel. There are another two storage screws on the upper level of the adder. The adding shaft at the back winds a screw similar to a grub screw up the threaded inside of the storage screw shaft. The slow to respond near side machinery detects the movement of the storage screw and starts rotating the storage screw shaft an action that works to return the storage screw to its rest position. The angular velocity of the storage screw shaft, is controlled by what George Julius describes as Variable Speed Friction Gear. This Variable Speed Friction Gear allows the storage screw shaft which has been likened to a nut to accelerate at a rate that inertia allows and achieves an angular velocity greater than that of the storage screw either through its maximum velocity being reached or a decline in the betting rate or both, resulting in the storage screw travelling back towards its rest position. The storage screw position sensing equipment, detects when the screw is nearing its rest position and provides feedback to the Variable Speed Friction Gear, to slow down the nut to produce a gradual gentle stop. On the subject of analogies with electronics systems, this sounds like a closed loop servo system. For the purpose of describing what seems apparent regarding the storage screw position sensing equipment, I will focus on the storage screw on the right hand side of the adder, although this generally relates to all the storage screws, where there are two storage screws paired together, some of the arrangement is the opposite way around. Part of the storage screw position sensing equipment consists of the rods extending from the centre of the ends of the storage screw shafts which act upon an associated lever extending vertically downwards from the right hand side of a pivot point above the associated storage screw pulley. The storage screw pulleys can be seen as nine pulleys in a horizontal row at a level below the lower counter wheels and display panel on the left. The left two storage pulleys are larger than the rest of the pulleys. The rod in our example is seen protruding slightly above and to the right of the right hand storage screw pulley. The storage screw position sensing equipment pivot points seem to have two levers attached to them that work together. In our example, the right hand lever attached to the pivot point above the storage screw position sensing rod, is the longer and its middle is connected to the storage screw rod which moves the lever. The bottom of this lever pushes on an adjustment screw contained in another lever pivoted from below the associated storage screw drive pulley. The upper lever pushes the lower lever and a projection on the lower lever seems to engage a projection on the storage screw drive pulley which seems to have the effect of locking it from rotating when the storage screw has reached its rest position. The left hand lever has a rod attached to it that disappears rearward down the left side of the storage screw and extrapolating its direction it looks like it connects to a lever that rises to a pivot rod running the width of the adder below the shelf that also runs the width of the adder behind the lower counter wheel. This rising lever then changes direction 90 degrees at the fulcrum, then travels rearwards and disappears from view behind a cable loom running up the nearest right hand pillar of the adder. This puts it in a position to connect with the activating arm of the right hand Mercury Pot Switch described next. This switch must cut off a circuit associated with the storage screw when the screw has returned to its rest position. The method of achieving this angular velocity control seems to have more than one form. In this adder it seems the variable friction is achieved by altering the tension on the drive belts. There are tensioner pulleys controlling the tension of the main drive belts. These belts run from the main drive shaft with its main drive pulleys, which can be seen across the bottom front of the adder, to the Storage Screw Nut Drive Pulleys arranged at 90 degrees to and above the Main drive Pulleys. The nine tensioner pulleys can be seen in a row between the Main Drive Pulleys and the Storage Screw Nut Drive Pulleys. The main drive pulleys are driven by the large double pulley near the middle of the Main Drive Shaft. I presume this is a double pulley to eliminate the possibility of a single main pulley belt failure causing a complete adder failure. The twin belts are driven by a twin pulley on a drive shaft underneath the floor. Is this where the computer room false floors originated? The tensioner pulleys are attached to levers dangling down from their fulcrums and some can be seen extending out to tension their respective drive belts. It is possible that the Variable Speed Friction Gear referred to by George Julius, in the case of this adder, is implemented by these tensioners however I cannot see from this photograph whether the extension of these pulleys is controlled by the storage screw position sensing equipment or whether they are just manually adjusted to a fixed position to take up slack originating from different length drive belts. One final observation about the belt tensioner mechanism. Attached to the adder frame, next to the top of each tensioner pulley, a short distance above the fulcrum, are what looks like threaded rods with springs on them, with a nut holding each spring on its rod. The rods project out in the same direction as the storage screw position sensing rods. It appears that the compression of these springs, determines the force applied to the drive belts, as each of the extended tensioner levers has its corresponding spring rod thread poking out through its nut, implying these nuts are compressing their respective springs to a greater extent than the ones where the threaded rod cannot be seen protruding from its nut. If this is how the tensioner arms are controlled it remains unknown whether these springs are tensioned manually or by the variable friction gear mechanism George refers to.

I have just noticed a device that Neville Mitchell, the best historian of this company I know, has described in the Video clips of a working Julius tote chapter under the Technology to shake to heading. The switching circuits he refers to can be seen in this adder. About half way up the adder, there is a shelf that runs horizontally across the adder. On the left hand side, the shelf is hidden by the lower counter wheels and display panel. On this shelf the mercury pots Neville mentions can be seen in pairs with the fork like spans inserted in the pots. Neville is writing about Giant Drum Julius Tote displays he saw in Thailand however the mercury pot switches he describes are clearly visible in this adder. Neville wrote they had switching circuits for the decade counting from one digit to the next which were mercury pots, with probably about a 25mm diameter pot 30mm deep that was filled with mercury lying side by side, and then a fork like a span, which was the switch, would dip into it, and that would create the circuit to the next decade. And you can imagine how absolutely accurate that was, there was no chance of a dirty contact or a miss-up in a norm transfer. There are nine of these mercury pot switches on this shelf the left hand two are hidden from view. There is one of these for each Storage Screw underneath this shelf. There is a pivot rod running the along underneath this shelf. There are levers on this rod with a right angled bend which pivot at the bend. In their present position they are oriented with one arm of the level vertically down the the other arm horizontally rearward. The bottom of the vertical part of this lever is controlled by the storage screw position sensing mechanism as mentioned in the text above. The rearward end of the horizontal part of this lever connects with a small vertical rod rising to join the back of the fork arm the prongs of which are sitting in the mercury pots. This fork arm is pivoted and this vertical rod acts to raise the fork arm out of the mercury breaking the contact. This is part of the servo system's means of bringing the associated storage screw to its rest position. One of these Mercury Pot Switches can be seen on this adder associated with the upper assembly which has two more storage screws. The Mercury Pot Switch is beneath the upper storage screws and to the left of the post with the number five and light on it. This is a good contrast with the other Mercury Pot Switches, as this one has the fork lifted out of the mercury and is in the off position.

When looking at any Julius adder, like this one, it is interesting to remember that you are looking at a piece of equipment capable of parallel processing, a modern computing concept. This old system through the Julius Adders, could do something that the digital computers I introduced on the Brisbane racetracks that replaced these Julius systems could not, parallel processing. I was often reminded of this by the staff I inherited who used to work on the Julius totes. If two or more of the Scanners (Time division multiplexers) on the Julius tote, selected TIMs (Ticket Issuing Machines) that had a transaction pending on the same runner, they would activate all the solenoids connected to these scanners at the same time, in the adder associated with the runner. These multiple escapement wheel activations are instantaneously registered by the epicyclic gears in the adding shafts. In the extreme, if every TIM scanned from the respective groups of TIMs on a scanner has a transaction pending for runner 5 for example, which is the runner the adder in this image represents as indicated by the 5 displayed on top of it, and they all happened to be scanned at the same instant, then all of the 39 escapements, mentioned above would be activated at the same instant and the total investment would be instantaneously recorded by virtue of the epicyclic gear trains. My new computer totes, although loosely coupled multiprocessors, were not capable of parallel processing. Each processor sequentially processed every bet and this transaction processing was first done by the master computer, which then passed transactions to the slave, to be recorded there, albeit that this happened so quickly that it all looked like it was happening at once. The Julius adders could record multiple bets instantaneously!

There is no photographer's stamp on this photograph.