Experimental Paper.-Whatman So. 1 was cut in strips 12.5 cm. wide and 44 cm. long across the fiber and dried for 1 hour at about 200". They were drawn through a solution of 5% silicone in ether (Don. Corning200 fluid, viscosity 10 cs.), airdried, and stored in a desiccator over calcium chloride. After such treatment, the paper is only slightly water repellent. Lipids.- The amounts of lipid applied to the paper should be adjusted to the particular problem. ...