This certainly seems a very strange doctrine, nevertheless the fact that Spain is but little subject to the plague seems undeniable, and as it is no less certain that the towns are excessively filthy, it would seem that cleanliness is not effectual in preventing it. But, however agreeable the smell of human excrements may be to the Spaniards, or to the English physicians in former times, it seems to be less so at present. “I am persuaded (says Dr. Ferriar) that mischief frequently arises from a practice common in narrow back streets of leaving the vaults of privies open. I have often observed that fevers prevail most in houses exposed to the effluvia of dunghills in such situations.” In Spain the opinion seems to have been but lately eradicated; for some years ago, an order having been issued by government that the streets of Madrid should be kept somewhat cleaner, the people were so much exasperated at being threatened with the loss of the savoury odour, that a rebellion had almost ensued, and the physicians declared the smell of human excrements to be the most wholesome thing in the world.[115] [115] It seems, however, of late, that at least the city of Madrid is kept clean. Swinburne says, speaking of the palace at Madrid, “To the west it has the town, the three principal streets of which terminate in the Pravo. These are three noble openings, excellently paved, and clean even to a nicety; indeed so are most of the streets of Madrid since the edict for paving and cleaning them.[116] The foreigners that resided here before that time, shudder at the very recollection of its former filth. Some of the natives regret the old stinks and nastiness; as they pretend that the air of Madrid is so subtil as to require a proper mixture of grosser effluvia, to prevent its pernicious effects upon the constitution. The extremes of cold and heat are astonishing in this place, and the winds so searching, that all the Spaniards wear leathern under waistcoats, to preserve their chests; for they pervade every other kind of clothing.” The former filthiness of Madrid, together with its being situated in a climate exposed to the vicissitudes of extreme heat and cold, and its exemption from the plague under those circumstances, certainly presents a most solid objection to the theory of the domestic origin of plague. To the same purpose see below the remarks on the climate of China. [116] Dillon has a like remark in his “Travels through Spain.”