The best known hot bath in this country is the one at _Bath_, in Somersetshire, the water of which proved so attractive to the Romans that they founded the city of _Aquæ Solis_ here, in the 1st century of the Christian era. It is needless for us to dwell upon the popularity of Bath. There are four hot springs here which vary in temperature between 120° Fahr. and 104° Fahr. The supply of water is ample and abundant, and the accommodation for guests such as can hardly be surpassed. The corporation of the city have lately erected a magnificent suite of baths, and if they will but turn their attention to the condition of the river Avon, and rigidly enforce the provisions of the Pollution of Rivers Act, Bath may again become as popular as it was in the days of Beau Nash. The elevation of Bath above the sea-level is only about 100 feet. The constituents of the Bath water are chiefly sulphate of lime with a little carbonate of iron, together with some free carbonic acid and nitrogen. It has been called an earthy water, but perhaps it is better to regard it as a simple hot water, the chief virtue of which is its warmth. _Buxton_, in Derbyshire, is situated nearly 1000 feet above the sea-level in an open hollow surrounded by hills. There is good reason to believe that the water of Buxton was known to the Romans. The temperature of the Buxton water is 82° Fahr. The amount of saline ingredients is but small. The water is, however, impregnated with a large quantity both of carbonic acid and nitrogen gas. The town is amply provided with accommodation both for bathing and lodging. At _Clifton_, near Bristol, there are springs having a temperature of 74° Fahr., and at _Mallow_, in Ireland, is a spring having a temperature of about 70° Fahr., and containing, like the water of Buxton, a large quantity of free nitrogen gas. A great deal has been written about the virtues of free nitrogen in water, but without, as it seems to us, sufficient evidence. There are many hot springs in Europe which are very largely frequented by invalids. We can, however, do little more than tabulate the chief, indifferent, and earthy thermal springs, giving the chief facts concerning each. At _Leuk_, in Switzerland, situated at the foot of the Gemmi Pass, we find a water possessing a natural temperature of 102° Fahr. to 120° Fahr., situated 4600 feet above the sea-level. The water is indifferent, and it is the custom here for bathers to remain many hours consecutively in the water. Ladies and gentlemen bathe in the same bath, and it is no uncommon thing for the bathers to be seen taking their luncheon or playing dominoes upon floating tables. At _Pfaffers_ and _Ragatz_, near the town of Coire, in Switzerland, are found indifferent springs, situated between 1500 and 2000 feet above the sea-level, and having a temperature of 100° Fahr.