One of the most interesting of land animals found in the north is the musk ox. When fully grown and in good condition this animal weighs five hundred pounds and upward. When the musk oxen are attacked by wolves or dogs they form themselves into a circle with their heads on the outside and conceal their calves under their bodies. Their hair, being long, reaches nearly to the ground and forms a curtain which completely conceals the calves from view. Their food is moss and lichens which grow on the rocks. This they obtain by scraping away the snow with their sharp hoofs. The flesh of the musk ox, though musk-like in flavor, is not repulsive to the taste, and several explorers have been saved from starving by using the flesh for food. The chief obstacles to arctic exploration are the long winter night, during which all must remain idle, and the necessity for carrying all provisions. No one who has not wintered beyond the arctic circle can have a realization of the influence on the nerves of continual darkness for months, an influence that has driven many men insane. Combine the darkness with the weird scenery and the fierce storms that prevail during the long winter, and it requires a strong will and abiding faith not to be seriously influenced. The extreme cold is not hard to endure if one clothes himself in the manner of the Eskimos. Provisions and supplies must be carried by dog sledges, and the management of the dog teams is very difficult for those who have not been trained to the work. Shetland ponies have been tried as draught animals. Captain Evelyn Baldwin was the first to use them in polar exploration; others have used them, but less successfully. Good coal is found in abundance on many of the islands of the arctic. Its outcroppings are found on Disco Island, west of Greenland, and excellent coal is found in many places in Spitzbergen, where at the present time two companies are mining it, one American and the other English. Spitzbergen is sometimes called No Man's Land, since Norway and Sweden have not been able to agree in regard to its possession. Lately the islands of this archipelago have become favorite resorts for summer excursionists who can here have the arctic scenery and experiences with but very few discomforts. Ptarmigan, geese, ducks, and many other kinds of birds are found on these islands. Large quantities of eider-down have been obtained annually from this section, but the rapid destruction of the ducks by hunters has lessened the industry and will probably annihilate it. There being no law to regulate hunting, sportsmen wantonly kill the wild animals, especially the reindeer and bears, in great numbers.