_Blue Black on Wool_.--Dye as in the last recipe, but use Acid (p. 090) Black S. This dye-stuff produces bluer shades of black than either B or B B, and they are faster to soaping. _Jet Black on Wool_.--Make the dye-bath with 4-1/2 lb. Acid Black S, 1/2 lb. Fast Yellow F Y, 3 lb. sulphuric acid, and 10 lb. Glauber's salt. This shows how, by the addition of a little yellow dye-stuff, the blue shade may be changed to a full jet black. _Blue Black on Wool_.--The dye-bath is made with 4-1/2 lb. Naphthol Black B (or 6 lb. Naphthol Black 3 B), 4 lb. sulphuric acid, and 10 lb. Glauber's salt. Work at the boil for one hour, then lift, wash and dry. The Naphthol Blacks have long been used in wool dyeing, and give excellent results, the 3 B brand dyeing much bluer shades than the B brand. There is also a 4 R brand giving violet blacks. These blacks are quite fast to acids and alkalies, are fast to light, and resist washing very well, the B brand being the fastest. The following recipe shows how a full jet shade can be obtained for these blacks:-- _Jet Black on Wool_.--Prepare the dye-bath with 4-1/2 lb, Naphthol Black B, 1 lb. Naphthol Green B, 1/4 lb. Indian Yellow, 4 lb. sulphuric acid, and 10 lb. Glauber's salt. _Blue Black on Wool_.--Make the dye-bath with 5 lb. Anthracite Black B, 10 lb. Glauber's salt, and 5 lb. bisulphate of soda, working at the boil for one hour. Anthracite Black does not require a bath so acid as do some other coal-tar blacks. The shade obtained is a full blue black, which is fast to acids; alkalies turn it a little bluer, and soaping causes some loss of colour. _Violet Black on Wool_.--Make the dye-bath with 5 lb. Anthracite Black R, and 10 lb. bisulphate of soda. The black thus obtained is a good one, fairly fast to acids, alkalies and soaping. _Dead Black on Wool_.--Make the dye-bath with 6 lb. Anthracite Black R, 1 lb. Anthracene Yellow C, and 10 lb. bisulphate of soda. Work at (p. 091) the boil for one hour, then lift, add 3 lb. fluoride of chrome and work again at the boil for twenty minutes. This black is a very fine one, and is very fast. _Violet Black on Wool_.--Make the dye-bath with 4 lb. Naphthylamine Black D, 10 lb. Glauber's salt, and 5 lb. acetic acid. This black is pretty fast to acids, alkalies and light, but is somewhat loose to soaping, and, therefore, cannot be used for black goods that have to be strongly milled. Naphthylamine Black 4 B dyes somewhat bluer shades than the B brand. _Blue Black on Wool_.--Prepare the dye-bath with 6 lb. Victoria Blue Black, 20 lb. Glauber's salt, and 1-1/2 lb. acetic acid, working at the boil for one hour. A fine blue black, is obtained which is quite fast to acids, washing and light. _Greenish Black on Wool_.--The dye-bath is made with 3 lb. Victoria Black Blue, 2 lb. Fast Yellow F Y, 20 lb. Glauber's, salt, and 1/1-2 lb. acetic acid. The dyeing is done at the boil and takes about an hour. This shade has a good full tone, and is fast.