A traveller should be supplied with suitable housing, food and clothing, and should have a proper supply of medicines, dressings, and medical comforts. In selecting the drugs with which the traveller should be provided before leaving home care should be taken to see that only reliable products be purchased. In the tropics, and in exploration generally, the medical outfit is subjected to very severe tests, and it is a mistaken policy to economise on medicines. The latter should be as portable as possible and be properly packed. _Risks to Health in a Tropical Climate._ Seeing that these hints will be chiefly required by travellers in tropical or sub-tropical climates, it may be well to indicate some of the chief risks which are to be met with in warm climates, and the best methods of meeting them. It will be noted that any detailed reference to questions of outfit, such as the supply of proper food or clothing, is omitted, as these matters have been fully dealt with in ‘Hints on Outfit,’ published by the Royal Geographical Society uniformly with this ‘Hints to Travellers,’ and it is understood that this work will be consulted by all who read these hints. _Chill._—The most prominent feature of a tropical climate is undoubtedly heat, and yet the greatest risk arises not so much from excessive high temperature as from a risk of chill, which is due mainly to the excessive perspiration which takes place. This must be guarded against by the use of proper clothing, the most important point being that the underclothing should be partly of absorbent material. For general use cotton is best, and the vest or undershirt should in the tropics be of the Aertex Cellular type. It is a mistake to wear wool next the skin in hot countries, for it soon gets sodden with perspiration and is irritating. A light flannel shirt worn over the open cotton mesh is probably the best arrangement though a mixture of wool and cotton may be employed for the shirting. This question is fully dealt with in ‘Hints on Outfit.’ It is particularly important to avoid sudden changes of temperature, and if exposed to the cooling sea breeze, special care must be taken as to proper clothing. Parke laid great stress on the importance of avoiding chills, draughts, or wettings. He remarked “In crossing Equatorial Africa the Relief Expedition found that every wetting meant an attack of fever.” The sea breeze, which is so refreshing and cool, by checking the perspiration, frequently acts as the exciting cause of an attack of fever. There is special liability to chill and subsequent fever when ascending an eminence, as the exertion causes profuse perspiration, and the cool breeze encountered on arrival at the top is very likely to produce ill effects. On completing a day’s journey, the underclothing, at least, should be changed without delay, and the skin should be well dried by the free use of a rough towel. If at all possible a warm bath should be taken.