Wengernalp SLM locos [ Snowdons twins]

I have often wondered if there were any identical locos to the Snowdon Mountain railways first series of locos as they were apparently 'off the peg' designs, I do know there is an identical loco to the second series that is actually preserved but of metre gauge [ I wonder if the loco is wider?] anyhow the Wengernalpbahn in Switzerland had four numbers 9 to 12. and the link is below, I couldn't find any reference to the works numbers though to gauge exactly the time frame of their construction.

http://schienenfahrzeuge.netshadow....24&sessionid=26d31aec25a48f2706f3064d96f8dc3b

I think the line drawing below the image has appeared in Boyds Narrow gauge railways of North Caernarvonshire, It looks identical.

 

They where basically the same between the two railways the Wengan ones show the short domes which where an issue at Snowdon at first. The main difference was in the drive which is unbalance with pivot at the bottom of the beam at the front where as the other preceding and later locos used the centre as the pivot . This giving an approximate 3/2 mechanical advantage. There is no visible speedo also on the Wengan locos where the snowdon ones had a speed recorder and an over speed indicator to a punched card. This at snowdon was later removed in the 1930's. un like the later Snowdon Locos they where all saturated boilers of around ten sq ft grates and consume about a ton of coal for a run up Snowdon. These locos are like a cart horse compared to the later ones of 1923 being like race horses. I am unaware of any other railway having other orders yet there are many Railways of that era which I am unaware of their motive power.

The Wengan locos had a short life due to electrification. Snowdon was at one time proposed to be electrified which never happened. To this day these older locos are the preferred ones to the more modern design.

 

Locos on the Montserrat line near Barcelona were very similar to later Snowdon locos. Two are preserved.