Elk
2 of the 7 encyclopedias on this shelf carry an entry for Elk. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
a genus of the deer family. The American elk or wapiti is really a large deer,--the largest and finest deer in North America . It is chestnut in summer and grayish in winter. It corresponds in the west to the caribou in the east. It is a stately animal nearly as large as the moose. It attains a live weight of 1,000 pounds. The antlers attain a spread of thirty to fifty inches. It has small, shapely legs, and hoofs fitted for hard ground. Like the deer it sheds its antlers annually. Its original range corresponded with that of the buffalo. It was once found from Virginia to Wisconsin and westward, but it is now nearly extinct. Possibly 20,000 still find shelter in and about the Yellowstone National Park . In the winter season they migrate southward to graze in the valleys of Jackson's Hole. There are small herds in the Olympia Mountains of Washington, in Oregon, California, Colorado, Montana, Idaho, and Manitoba. Fortunately, elk do well in parks. A herd of sixty-two has been set free in the Adirondacks. Mr. W. C. Whitney built up a large herd near Lenox, Massachusetts. Twenty or more American cities have herds in their parks. The real American elk are the moose and the caribou--flat-antlered animals. The remains of a huge elk have been found in the peat bogs of Ireland. The tips of its enormous antlers are eleven feet apart. See Deer
Collier's New Encyclopedia (1921)
MOOSE, or MOOSE DEER, the largest of the deer family, a native of northern Europe, Asia, and America. The American form (to which the name moose is usually given), is sometimes separated from the European, but most naturalists find no specific difference between them. The elk or moose has a short, compact body, standing about 6 feet in height at the shoulders, a thick neck, large, clumsy head, and horns which flatten out almost from the base into a broad, palmate form with numerous snags. In color the elk is grayish brown, the limbs, sides of head, and coarse mane being, however, of a lighter hue. The moose has a wide range in Canada, extending from the Arctic Ocean, and British Columbia, to New Brunswick and Nova Scotia; it is found also in Maine. It feeds largely on the shoots of trees or shrubs. In Sweden its destruction is illegal, and in Norway there are many restrictions.