Capes Deep Indigo Very little matter, pure 14 Off Cape Finisterre Undecided Less pure 15 Bay of Biscay Indigo Very little matter, very pure 5 Off Tarifa Undecided Thicker than No. 4 6 Beyond Tarifa Cobalt-blue Much purer than No. 5 7 Twelve miles Yellow-green Thick, but less so 4 Off Cabreta Point Bright green Much less thick from Cadiz 11 Between Capes Deep Indigo Very little matter, very pure 16 Bay of Biscay. Calm spaces of blue, instead of using my breath communicated to the greatest "limit of error" allowed. [Illustration: FIG.