CHAPTER XII.
1. SANITARIA.—I come now to treat of medical certificates, and the different plans resorted to by European officers when change of air is thought advisable. To an invalid labouring under chronic disease, and exhausted by slow but long-continued fever, change of air, as it is commonly called, brings about the most wonderful effects. I do not pretend to explain how this change operates, or to demonstrate whether there is any actual difference between the atmosphere of the twoplaces; or whether the good effects are indirectly produced by working upon the mind alone, but well assured I feel of its great efficacy in the restoration to health when convalescence has begun; as also of its giving a favorable turn to disease before convalescence has begun. Change of air, from a good to a bad climate, is often attended with advantage; and this is evenperceptible in removing from one house to another, from one room to another, or further still, from one bed to another. For the correctness of these remarks, I appeal to every one who has had the misfortune to suffer from long illness.
