 Over its life the NSR built or bought many thousands of goods wagons . Early wagons had dumb buffers with spring buffers being introduced from 1870 . Early wagons were not of high capacity e.g. typical open wagons were only of 4 long tons ( 4 @.@ 1 t ) capacity. but capacities grew to 10 long tons ( 10 t ) on average by 1923 . 
