Scientific American 41, 3.7.1847

We are often puzzled at the amount of false receipt which we see daily published in various papers, most of which are perfectly useless. No receipt ought to be published confidently, unless it has been the subject of experiment. There is one thing which we are sorry to see and which they display, viz. a great and universal want of science. We have see na receipt for making wood incombustible by a mixture of soda, flour paste, and clay. Alum and soda alone possess the incombustible qualities, without the use of the plaster. Alumina is the basis of all clays. Again, we have seen in more than one paper, a great number of receipts on coloring, purporting to be new and discovered lately in London. To dye an orange, the receipt says, "take curcuma, tartar and the muriate of tin and boil five minutes" (the goods.) "To dye green use the same stuffs only add chemic blue," that is sulphate of indigo, "and boil the same lenght of time as for yellow." This is destruction indeed. The muriate of tin will destroy entirely the effects of the chemic, and silk will take on no color by boiling. We say never boil silk to dye it. Another receipt for cotton black says, steep the cotton in the chloride of lime is the stuff used to bleach, discharge colors, not dye them. To those of our mechanics' or farmers' wives or daughtersm who wish to dye silk, we say, never boil it, but use the dye at a good heat. We will shortly give a number of receipts on dyeing and the method of using them and will recommend the same as practical, cheap and in successful use by the best dyers.

Again, we perceive in a co[n]temporary paper, a receipt for making incombustible paper, by infusion in a dilute solution of alum and gunpowder." Such utter ignorance of chemistry! What use is the gunpowder as it regards an incombustible, unless it be just to destroy by its combustible qualities, a portion of the incombustible quality of the alum.

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