_Wax_ is a softener used for light sizing with farina. It is of two kinds: Japan wax, a vegetable substance, of rather yellow colour, and paraffin wax, clear and semi-transparent, obtained from mineral oils. A high melting point of wax is a great desideratum, to ensure the mixture hardening thoroughly on the warp--110° is considered a fair temperature for wax to bear before melting. For softness, castor oil and glycerine are occasionally adopted, as is also Irish moss. _Soap._--A mixture of animal and mineral substances is not generally used, although a good softener, its frothy nature when boiling rendering it difficult to deal with. Soap and chloride of magnesium (so called anti.) should not be used together, as their action on each other tends to make the size lumpy. One important property of soap, or rather alkali contained in it, is that it kills any acid developed in the mixing. Soda has a similar and stronger tendency. Chloride of magnesium, muriate or chloride of zinc have softening properties, but those substances will be more fully mentioned in the next group. _Weight-giving Material._--Next to flour no substance enters into heavy mixings in such quantity as _china clay_. This is a white earthy matter found in Devon and Cornwall. After having all stony substances washed out it is dried and packed in bags for shipment to Runcorn and other small ports in the neighbourhood of cotton manufacturing districts. In selecting good qualities, colour and smoothness should be borne in mind. To use this material to advantage a good knowledge of other materials is required, so that such ingredients may be used with clay as to keep the size on the yarn at the loom. When clay is boiling it is somewhat dangerous to lift up the lid of the boiling beck, this substance having an unpleasant property of spurting up, possibly on the face or hands of an attendant. Metal size is that containing the chlorides of the metals, magnesium and zinc. Chloride of magnesium, a mineral salt obtained in Germany, is valued as a weighting and softening compound. It has the peculiar property of attracting moisture to itself, always causing cloth or any substance containing it to feel damp. This substance is melted out of its solid form into a liquid by the application of steam, and is afterwards stored in a lead-lined tank. Muriate of zinc, or chloride of zinc, is a substance of importance for weighting, and is also valuable in checking the growth of mildew.