historical notes on mechanical loaders

hello around there are several topics and articles on the history of mechanical shovels, but for example which was the first hydrostatic mechanical shovel, better hydrostatic or power shift with torque converter converter, the caterpillar volvo the jcb as the progenitor. such as the first hydrostatic, tracked or wheeled, let me know or give me some article thanks.


http://publiquip.com/news/Volvo-Wheel-Loaders.htm