If this precaution be taken and if the colors are prepared according to their relative expansibilities as they are used in the order prescribed, the process will not meet with any obstruction or difficulty. As the size plays such an important part in marbling, great attention must be paid to its preparation if it is desired to make a good base for the colors. I especially recommend to laymen that they direct their attention to the consistency of the size, as this is always the key to the production of good edges. The different peculiarities of the varieties of sizes, viz; evaporation, influence of temperature, starry formation of colors, formation of angular scales in comb-edges, and all other things which have influence on colors, will be treated of in a special article on the varieties of size. CARRAGEEN MOSS. CARRAGEEN MOSS. The Carrageen or Iceland moss, or lichen is one of the algae of the sea. Chondrus Crispus grows on the cliffs of the Atlantic Ocean and the North Sea. Carrageen smells slightly of iodine and when uncleaned tastes offensively salty. Like all seaweeds it contains a great quantity of mucilage and small quantities of salts of iodine and bromine. When washed in sweetened water it becomes nearly tasteless and is without smell. On account of the great quantity of mucilage contained in it, and of its action as an alleviative to pulmonary complaints it has found many applications in medicinal practice and is given to the patient boiled in water, milk or bouillon or as gelatine in cases of coughs and diarrhoea, being a slightly nutritious substance. The carrageen moss or Iceland moss or weed is a lichen and consists of a tuft of flat deeply divided cartilaginous fronds of an olive brown, sometimes yellowish or reddish white color; the tuft is sometimes 2 to 5 inches long. The moss is used in many ways; as size for marbling edges, for clarifying beer, as linen-weavers starch, for finishing cloth and in the production of iodine. The good pure carrageen is horn-like, yellowish-white, contains a great quantity of mucilage and gives the best size for marbling, as it complies with all the requirements of a good size. It is homogeneous, of great consistency, not extraordinarily viscous and cheaper than all the other materials containing mucilage which are used for marbling, but is inferior to gum tragacanth as far as durability is concerned, and that it must be subjected to boiling, but this trouble is amply repaid by the beauty of the productions. On this size all varieties of edges can be produced, and by its diaphanous watery mucilage it gives an excellent ground to work upon.