'The Swift frigorífico'
The owners were almost immediately taken over by the Swift Beef Co, and it is as the 'Swift' plant that the frigorífico was known for the rest of its life. It survived until the 1970s, but the derelict buildings remain, as seen below.
Within the abandoned frigorifico track survived until nearly 2010 before being cleared, as seen below.
The plant had one steam locomotive, an Avonside 0-4-0T, no. 1592 of 1910. This also still survives, though in an extremely poor condition.
The drawing was taken from an Avonside catalogue of the 1920s. The loco was of their class NB. This was a small design, weighing only six and a half tons in working order, and available for gauges between 2' and 3' 6" (1). Whilst the Swift loco was an 0-4-0T rather than an 0-6-0T it seems likely that the overall wheelbase was not all that different.
This view of the engine by itself was taken by Richard Campbell one evening when the sun was low. 
This is the only view which has so far come to light of the railway in operation. Its author is Jorge Prinos who worked for Swift, being in charge of all their machinery. The view was found on Facebook. 
The photo below shows it in 2000, in the local museum's outdoor facility near the big roundabout that was at the time on the southern outskirts of town. More recently it has been moved (along with the RFIRT's Henschel 0-8-0CT) to the Amigos del Tren compound near the old RFIRT loco shed (2).
A single flat wagon lay near the loco, both at the roundabout and now in the museum, where in 2014 David Sinclair crawled underneath it. It had seemed likely that this came from the Swift plant, despite the chopper coupling. However, underneath, it was clear that it had originally been metre gauge, but was now 75 cm gauge. It would thus appear that this may have been an ex Central of Chubut wagon which had been re-gauged at the Bahia Blanca North Western works for the Río Turbio line.
Note how the spring does not bear directly on the solebar, as it would have when new.
The Swift muelle had a rail-mounted steam crane on it, of unknown gauge though almost certainly wider than the 3' 6" of the main frigorífico system.
The following photo, by Señor Walter Roil, shows the steam crane lifting a load of sacks from what may be narrow gauge wagons on the muelle. [This photo belongs to an unrelated website, which can be accessed directly by clicking on the image.]
This is a view of the complete Swift muelle at low tide showing the steam crane at the shore end. 
Río Gallegos seems to have had additional narrow gauge railway tracks along its foreshore, probably of 60cm gauge and linking to the 'Enosis' muelle.
These two pictures were taken by Señor Walter Roil, a professional photographer in Río Gallegos. The one above was taken in 1940 and the other in 1935. [These photos belongs to an unrelated website, which can be accessed directly by clicking on the images.] More recent (2016) information from Río Gallegos suggests that this line was operated by the La Anonima (full name La Sociedad Anónima Importadora y Exportadora de la Patagonia), the Braun-Menéndez conglomerate, in connection with the wool exporting side of their business.
The two photos shown here were taken from Argentina Austral magazines of the 1920s. They were taken on the occasion of carcases from estancias Bella Vista and El Cóndor being loaded for shipment north in the steamer José Menéndez. 60cm gauge railway tracks can be seen in both illustrations.
A final photo by Señor Roil was taken in 1935 when the Australian polar explorer Sir Hubert Watkins was flying to Antarctica. This shows some rather heavy weight track along the foreshore, made up , most unusually for Argentina, of bullhead rail in keyed iron chairs. This may well be part of the Swift system. [This photo belongs to an unrelated website, which can be accessed directly by clicking on the image.]
The big estancias and 'frigoríficos'