100 years ago, construction started on Trans Australia Railway. The work continued through WWI (known as Great War then: it wasn't WWI until WWII came along).
Track laying was highly mechanised for the era, including world records for distance laid in a day.
Earthworks used animals.
My memory is of horses rather than camels: there is a wonderful documentary which I have seen many times and at many places, but I can't find it online.
They hauled scoop skips which grabbed up soil, then hauled them to a dumping spot, where the driver upended the skip like a wheelbarrow. They were used two ways: to grab earth/gravel to build up an embankment for the track, and to create dams to hold bore water for locomotives. These were roofed, to reduce evaporation.
The only video which I can find fast has two glimpses of horses. In one of them, two horses are hauling a foreman's buggy.
The centenary of the first sod at the eastern end was celebrated in Sept.12 at Port Augusta (SA); the centenary of the first sod at the western end will be celebrated in Feb.13 at Kalgoorlie. I have placed an advance alert in the events thread, as it would be a great weekend for anything vintage to rally to Kalgoorlie.
Rail Heritage WA is renovating rollingstock from different eras (including some 1917 originals) to provide a heritage train for the centenary of completion.
Horse works, latest project. Poles went across the big gear, up to four horses worked around in a circle, a long shaft from the u joint to a pulley outside of the horses path.
Bevel gears 4 to 1, spur gears 5 1/2 to 1 giving 22 revs for one from the horse. Have never seen one in action.
I was at Wonthaggi (Vic.) on the day when the last pit ponies were brought out of the closing black-coal mine (Dec.6*). I don't know what the spell of duty was below the surface, and it may well have been a whole working life. Gooey newspaper readers were warned not to offer to adopt one: they had the wrong temperament. It seems that they were brought out after every shift, or perhaps on a weekly rotation. There are many references by googling. One which keeps giving downloading errors reports an event when fire caused the failure of the main lift. The pit ponies had to be brought out through a ventilation shaft: ok for miners, but not the right size for horses.
I have stacks of books and magazines from Light Railway Research Society of Australia showing horse teams hauling logs on forest tramways; the were the norm, rather than the exception.