It was about the middle of March, which is the most disagreeable month of the whole year in this country; yet I found the weather very mild and pleasant. Light showers of rain happened almost every day; but these lasted commonly but a few minutes and were succeeded by warm sun-shine. I could discern the Appenines at a distance, covered with snow, while the hills around the city were decked with green olive trees. Oranges and lemons were plenty and very cheap: three or four for a cent. I set out on a walk to visit the famous _grotta del cane_, or “dog’s cavern,” which is only a few miles from Naples. The road lay through the grotto of Pausilippo, and I could not avoid again admiring this wonderful cavern, the work of men who lived in what we have supposed to be an age of barbarism. At the further end I emerged into the open air and found a region of fields and vineyards, separated by walls of clay. Little children ran along by my side, tumbling head over heels, clacking their chops, making queer noises and antic gestures by way of begging for coppers. All along the road were poplar trees, to which the vines were trained, but they were not in leaf. After a walk of three or four miles I came to lake Agnaro, a piece of water about the size of Fresh Pond in Cambridge. On the shore of this lake is the _grotta del cane_. It is a rocky cavern which enters horizontally a little above the water, and emits from its mouth a sulphureous steam or vapor, which will kill a dog if he is put into the cavern. People who live in the neighborhood keep dogs for the purpose of exhibiting this phenomenon to strangers. The dogs know the fatal properties of this cave, and refuse to go in. While I was there, some of these fellows came to me and offered to exhibit the experiment; but I declined, not wishing to see an animal treated with cruelty for mere curiosity. They assured me that the dog need not be killed--that they would only keep him in the cave long enough to throw him into a swoon, and then bring him to life again by plunging him into the water. I told them this was as bad as killing him outright: for the animal could suffer no more by actually dying. They were very unwilling to lose their expected fee, and answered me that there was no suffering in the case, but, on the contrary, the dogs were very fond of the sport! I laughed at this impudent falsehood, and refused to have anything to do with the exhibition.