A technique for stabilizing droplet spots on oil-sensitive paper

The article describes a technique that was effective in stabilizing oil spo ts, deposited on oil-sensitive paper The technique involves the use of acet one vapor and could be used indoors or in the field. Treated targets were v ery stable and the size, shape, and color of the spots did not change in mo re than a year Air temperature, relative humidity, and solar radiation did not affect either dimension or color of the oil spots.