A room apart, somewhere away from the studio of design and the rooms where the looms stand stolid, is a laboratory of dyes, a place which looks like a farmhouse kitchen on preserving day. You sniff the air as you go in, the air that is swaying long bunches of pendulous colour, and it smells warm and moist and full of the suggestions of magic. Over a big cauldron two men are bending, stirring a witches' broth to charm man's eye. One of the wooden paddles brings up a mass from the heavy liquid. It is silk, glistening rich, of the colour of melted rubies. Upstairs the looms are making it into a damask background onto which are thrown the garlands Boucher drew and Tessier loved to work. Dainties fished up from another cauldron are strung along a line to dry, soft wool and shining silk, all in shades of grapes, of asters, of heliotropes, telling their manifest destiny. And beyond, are great bunches of colour, red which mounts a quivering scale to salmon pink, blue which sails into tempered gray, greens dancing to the note of the forest. It is a nature's workshop, a laboratory where the rainbow serves, apprenticed. Jars, stone jars, little kegs, all ugly enough, are standing against the wall. But uncover one, touch the thick dark stuff within, and feast your eye on the colour left on a curious finger-tip. You are close to the cochineal, to indigo, and all the wonderful alchemy of colour. Aniline? Not a bit of the treacherous stuff. It takes the eye, but it is a fickle friend. They say a mordant has been found to stay the flight of its lovely colours. Perhaps; it may be. But what weaver of tapestry would be willing to confide his labour to the care of a dye that has not known the test of ages? Aniline dye, says the director of a tapestry factory, may last twenty years--but twenty years is nothing in the life of a tapestry. Over in Paris, at the Gobelins, a master rules as chemist of the dyes, with the dignity of a special laboratory for making them. In America, with no government assuming the expense, the dyes are bought in such form that only expert dyers can use them in the few factories which exist. But no new hazards are taken. The matter is too serious. Economy in dyes brings too great disaster to contemplate. It is only too true that a man, several men, may labour a year to produce a perfect work, and that all the labour may be ruined by an ephemeral dye, by the escape of tones skilfully laid. Let commerce cheat in some other way, if it must, but not in this. Let the dye be honest, as enduring as the colours imprisoned in gems. [Illustration: BAUMGARTEN TAPESTRY. MODERN CARTOON]