the lungs but little used in ordinary life are brought freely into use,--one is forced to breathe deeply, thus the vital capacity is enlarged, and, by favoring exercise of little-used parts banishes the tendency to disease from one of the seats of life. This so-called diaphanous rarefied air is not air, it is a celestial ether; and so with the sun, though it is hot, what you feel is not heat, it is a permeating, invigorating, life-creating warmth. This warmth, then, which the sun imparts to this ether pervades your lungs, your heart, and reaches to your very bones. This virginally pure air makes you conscious of a lighter and of a quicker life, an unknown facility in breathing, and a lightness of body. Its electric freshness is a brilliant vitality,--it is rest, inspiration, resolve. Then you are surrounded with pine forests, and the bright sun is constantly raising into the air from their trunks, branches, and leaves myriad molecules of their resinous exudations. On ascending a mountain the mean annual temperature decreases on an average of one degree Fahrenheit for every three hundred and forty-nine feet. The value of fresh air and exercise is a sentiment possibly as old as humanity itself. It is the same spirit which animated Hippocrates and Galen when those classic worthies discoursed upon the art of nature-cure. We really travel in circles in the case of disease-cure, as in most other things. None the less may we be thankful that, in our circular search after knowledge, we have come upon the beaten track of ancient days, and have enlarged the wisdom which of old showed forth the benefits of a cloudless sky and a pure ether.