. The silver sunbeam : a practical and theoretical text-book on sun drawing and photographic printing. 554 DEFECTS AND BEMEDIES. Fig. and pour the bath into it. This will precipitate considerableiodide of silver, which must be filtered out. Then boil the bath down to the originalamount, having first neu-tralized it with a little am-monia or bi-carbonate ofsoda ; stand it in the sunfor a few days. Subse-quently, if necessary, adda very small quantity ofnitric acid. Large, semi-transpar-ent places occur some-times when the developeris poured on. This is oc-casioned by a lack ofacetic acid i
. The silver sunbeam : a practical and theoretical text-book on sun drawing and photographic printing. 554 DEFECTS AND BEMEDIES. Fig. and pour the bath into it. This will precipitate considerableiodide of silver, which must be filtered out. Then boil the bath down to the originalamount, having first neu-tralized it with a little am-monia or bi-carbonate ofsoda ; stand it in the sunfor a few days. Subse-quently, if necessary, adda very small quantity ofnitric acid. Large, semi-transpar-ent places occur some-times when the developeris poured on. This is oc-casioned by a lack ofacetic acid in the devel-oper. If the bath shouldnot be sufficiently iodized,the iodide of silver formedin the film is dissolvedout, commencing at the edges of the plate. Plates that arekept too long before development sometimes become injuredby the increased strength of the silver solution, caused by the evaporation of theFig. 40. water, and the iodide of silver as in the formercase being partially dis-solved, and the coatingthus rendered thinner. 10. Comets, etc., Are intense opaque spots,which are not observedgenerally before develop-ment. Th
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