Whar's the source of the Argentinian 'Garratt' picture?
If could find more pictures, without a loco in the way, it may answer some of the questions..
Wicked-pedia helps a little:
Modified Fairlie locomotives[edit]
The Modified Fairlie was first introduced in South Africa, when the
South African Railways (SAR) experimented with a modified type of Fairlie locomotive in order to compare the concept to that of the Garratt locomotive in terms of actual performance and maintenance requirements. In essence, the Modified Fairlie was an adaptation of the
Kitson-Meyer concept. It was similar in appearance to a Garratt, but with the boiler, cab, coal and water bunkers all mounted on a single rigid frame which pivoted on the engine units, with the pivot centers located approximately at the centre of the rigid wheelbase of each engine unit. In the Garratt design, by comparison, the coal and water bunkers are mounted directly on the engine units and swivel with them, while the boiler, firebox and cab are mounted on a rigid frame which is suspended between the two engine units.
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Union Garratt locomotives[edit]
The Union Garratt was a hybrid locomotive, part Garratt and part Modified Fairlie, designed and built for the SAR by
Maffei in Munich, Germany. The front end of the locomotive was of a typical Garratt arrangement, with a water tank mounted on the front engine unit’s frame, while the rear end was constructed in the Modified Fairlie fashion, with the coal bunker mounted on a rigid extension of the locomotive’s main frame and with the pivoting rear engine unit positioned beneath the coal bunker.
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