. . .est character, is not to be excelled, though the addition of some soluble salts may be advantageous, particularly in dry climates or in very dry weather. Such salts are found in sodium nitrate, or ammonium nitrate, as much as equal weights of either of these substances being added. Thus our formula would stand as follows were these additions made:—

Original Solution. 1.— Silver nitrate 50 grains Water 1 ounce Modified Solution. 18 2.— Silver nitrate 50 grains Ammonium nitrate or sodium nitrate 50 " Water 1 ounce

The reason of the addition of the ammonium or sodium nitrate is that prints are better obtained on paper which is not absolutely free from water. When very dry, the liberated chlorine (see pa. . . Read More