of the flat dishes, a dilute solution containing pyrogallic acid, soda, and potassium bromide. The excellence of the result largely depends on the due proportion between these constituents, and here more experience is perhaps necessary than in any other part of the process. The image having been fully developed, the plate is well washed, and then immersed in a solution of alum, which hardens the film. After another thorough washing it is “fixed” by immersion in a solution of sodium hyposulphite, which dissolves out the unchanged bromide of silver, and, being once more well washed, it is finished, and must be set up in the rack to dry spontaneously. On no account must heat be applied, not even the warmth of sunlight, or the wet film will melt. When dry it must be varnished to protect the film. The printing operations are best deferred till the return home, as they would involve the carriage of a large amount of extra apparatus. It is generally best to get the printing done by a professional printer; but if the traveller prefers to print from his own negatives he will find full instructions in each packet of paper which he buys. Colour sensitive plates are now much used and, when a yellow glass filter is placed immediately in front of, or behind, the lens, will give in the print the same variations in depth of tint which the eye sees in the landscape, or other object. The nearest to perfection among these plates are those known as Panchromatic, but they must be developed in total darkness. The subject is a large one and should be studied in the pamphlets on ‘orthochromation’ published by Kodak (Wratten Division), and Ilford, Ltd. As regards the expense of a photographic outfit, at the present time the manufacturing trade is still very unsettled, some goods cannot be supplied, and all have been greatly increased in price. Quarter plates which used to be sold at a shilling per dozen are now about 3_s._ 6_d._ Application should be made to the dealers for current prices. The camera, slides and lenses may be arranged to pack into a solid leather case, conveniently in the form of a knapsack, measuring about 16 in. wide, 12 in. high, and 5 in. deep. This can easily be carried on the back of one man, and is of a more convenient shape than the cases generally sold for the purpose. The plates and other apparatus, with the exception of the knapsack and its contents, and the tripod stand, are best packed for travelling in a strong basket, which is much better than a box, being more elastic and lighter. It will weigh, when packed with the apparatus, and a gross of 7½ × 5 plates, about 60 lbs. _Photography in Natural Colours._