The New Zealand Railways Magazine, Volume 10, Issue 10 (January 1, 1936)
Stains
Stains.
Mud must be brushed off carefully when dry, and any remaining marks should then be covered with a fine paste of methylated spirit and pipeclay, or, for more obstinate stains, use boracic acid and ammonia. This should be allowed to dry and then brushed off.
Grass stains are removed by gently sponging them with a weak ammonia solution.
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