We made a number of visits to St Thomas over the years.
We particularly enjoyed this visit 'at the turn of the century'
during a celebration of the local railway heritage.
Live steam locomotives were featured..
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| from: CNR employee timetable 51, Southwestern Ontario Area, October 1973 |
This elegant employee timetable map shows St Thomas within the CNR network.
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| from: Atlas of Canada; 1915; Government of Canada. |
Railway territories are shown in this federal map of the railway lines circa 1915.
Consistent with local tourist lore, I think you can see the five railways of St Thomas.
The US lines owned/leased these fast shortcuts north of Lake Erie as part of their larger networks.
Essex Terminal Railway Company, Engine 9 (MLW 1923).
There was too much to see, so we didn't ride this time.
The substantial two-storey station once belonged to the Canada Southern,
the route of which is shown as Michigan Central on the map above.
Above: You can see one of a small group of hostlers and 'watchmen' who were attending this locomotive as it simmered here during our visit.
I think Reading 2100 was owned by Tom Payne at this moment in history. It had been designed to burn anthracite coal, but was converted to oil - an easier fuel to procure and handle at the turn of this century.
According to 'the internet' oil could not provide the concentrated heat of anthracite and the locomotive was deemed to be a candidate for conversion back to coal so it could be used economically in passenger service.
... Nonetheless, this kept happening.
On the west side of the shop, here is some of the specially-marshaled rolling stock for this event. There were speeder-trailer rides offered to the east and west at the same time on a particular track. Riding an unsprung trailer on bolted rail was a little rougher than a Turbotrain ride.
The location of the transfer table can be seen here at the east side of the shop.
The GTW (Port Huron built) caboose owned and restored by Ross Robinson at the Smiths Falls Railway Museum was displayed ... and showing the great care he took to see it preserved, restored and finally housed indoors. It had arrived during the previous year or so.
It was difficult to get a 'long shot' of the caboose inside the shop. The carefully-matched Morency orange is 'off' a little in the photo because I fiddled with the exposure so you could see the archbar trucks. At any rate, I tried to take a few photos to give to Ross if only to acknowledge all the work he did to prevent the car from being burned in Toronto - with only its metal hardware saved from the remaining ashes.
On February 17, 1991 my father and I made a trip up to Smiths Falls to commemorate
the 100th birthday of Ross Robinson's GTW caboose - as Ross was away at San Diego.
It was a crisp, cold winter day. I mailed a copy of this photo off to Ross.
With characteristic humour and exaggeration Ross said some of the Americans were amazed !!
Did we need to use a specially-heated camera to get the photo under those winter conditions?! etc, etc.
This CNR employee timetable gives you an idea of some of the local railway features of St Thomas.
A local roadmap appears below to show more detail.
The shops occupy the streetless area between Wellington Street and Talbot Street/Highway 3.
West of the shop area:
BX Tower (not shown on the map, but you can see some of 'its' tracks) is located just north of the intersection of Moore and Centre Streets. Its rectangular hip roof can be seen on the Google Maps satellite view in 2020.
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from: London, St Thomas roadmap, Rolph-McNally, no date. Purchased circa 1985.
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Taken from a caboose cupola, we are taking a 'shuttle' over to BX Tower
- at the right side in the distance.
It is described in the Talbot Subdivision timetable footnotes of the employee timetable above.
At BX Tower:
Our shuttle was pulled by Wabash 51 - a 43 tonner, built by GE in 1939.
This view looks east and you can see the Reading engine, etc.
Above and below, at the operator level of BX Tower.
Above is the operating side of the levers, along with our guide.
Below is the back side of the rack holding the levers.
We were shown the mechanism in the level below this, but a good photo was not possible.
The levers are colour-coded by function ...
e.g. lock, switch, signal etc.
There are excellent YouTube videos which interpret preserved
British interlocking towers (aka 'signal boxes').
Some of them also had separate levers to apply 'fog signals' (torpedoes) to the tracks.
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Photos of British Interlocking Systems
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| from: Railways in Camera; Robin Linsley; 1996; Alan Sutton Publishing. |
Stratford Central Junction, UK, photographed in 1912
... While BX [interlocking] Tower didn't show any evidence of electrical gear, the British 'signal box' above shows some.
As a generality and as I understand, British steam locomotives used lanterns placed in different locations on their pilots to convey type of train and route/destination. Of course, operators would expect the daily trains at particular times and their centralized train dispatching bosses would control the big picture.
The signal boxes (including the one above) would have simple 'telegraphs' connecting them to the next box 'UP' (toward London) ... and the next box 'DOWN' (from London).
Some early Canadian railways (e.g. GTR) also used the UP and DOWN system before the cardinal compass directions were written into the rulebooks and employee timetables.
Signal box 'telegraphs':
A bell circuit enabled a tower to initiate a call to an adjacent tower. When the distant tower answered back with the same bell signal ... a traffic request would be made with another bell signal. If concurred with, the adjacent tower would repeat that traffic bell signal back. A series of needle telegraphs would be used to communicate block occupancy between towers.
The paramount safety task of the signal box was to prevent a train from blasting by, and along the track beyond, before the next signal box indicated that the last train sent had cleared the block.
... There were rules to handle trains delayed for an unknown reason within the block and other exceptions to smooth operations.
The 'local autonomy' given to signal box operators is an interesting way to efficiently move traffic along a railway. It contrasts with the North American model where the dispatcher is often styled as a great military commander planning hours ahead, sending written telegraphic orders to 'his troops' in the field.
... I suspect this was due to the mainly 'single track through wilderness' infrastructure of North America. In contrast, the UK often had separate UP and DOWN lines, as well as stretches where there were Pennsy-style dedicated fast and slow tracks in each direction as well.
As Stratford UK (above) was a junction, one would expect at least 5 tracks to be converging on it from 3 or more compass directions ... so it is quite an operation. If you check the 'Stratford Station' (for the city near London) UK entry on Wikipedia, you'll see an interesting map of the local railway lines from 1914.
Often interlockings (e.g. Westmount, Quebec) governed movements around coachyards and passenger stations with multiple tracks.
I did a few pieces on the international development of telegraph signalling and the post linked below elaborates a little on this era of telegraphy.
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| from: GWR Company Servants; Janet KL Russell; 1983; Wild Swan Publications. |
Both photos:
At the Reading signal works of the Great Western Railway, UK, a signal box locking frame in construction for Aber Jct in South Wales.
I only have the upstairs views of BX Tower at St Thomas, but here you can get an idea of what was downstairs. Essentially, these railway signal workers are doing 'in house' computer 'logic programming' with metal. On both photos you can see a supervisor with a paper plan of how the algorithm and its language should go.
... from the Standard Code of the Association of American Railroads (AAR) in 1897 ...
"Interlocking: An arrangement of switch, lock and signal appliances so interconnected that their movements must succeed each other in a pre-determined order."
... by 1938 ... the AAR Standard Code language had changed to include that an Interlocking could be operated manually or automatically.
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| from: GWR Company Servants; Janet KL Russell; 1983; Wild Swan Publications. |
While the photos above do not show the linkages in detail, you can get the idea that this was a very complex logic machine ... which would then be connected to metal systems of rods, levers and cranks to actuate switches and signals far beyond the confines of the signal box at Aber Jct, South Wales.
In contrast to today's computer programming for standard hardware, a significant amount of mechanical engineering technology skill would be necessary to ensure that all the mechanisms operated smoothly as built here ... and when installed in the field ... to ensure consistent operation and necessary safety redundancy.
... There was generally a very specific prescribed sequence of lever operation to get a train from point A to point J through the interlocking. Locks, switches and signals were actuated along the planned route of the anticipated train movement one after the other until the operator had everything lined.
... Experienced interlocking operators (and maintainers) would develop an intimate knowledge of the operation and idiosyncrasies of their local equipment - particularly in all types of weather.
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From Jim Christie came a reminder of this fabulous article.
It shows how old interlocking towers were modified
to take advantage of advances in electronics.
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Further misadventures during our earlier visits to the St Thomas area can be seen through these links.
Near London in 1992 and the Loop Line Transfer
