This Siberian tundra is the coldest region in the world. The earth, alternating in many places with strata of solid ice, is hard frozen in perpetuity for a depth of several hundred feet. The mean temperature of January is -65°, but the interior is much colder than the sea coast, there being a difference of 20°. At Yakutsk -79° has been recorded, but the greatest natural cold ever measured is -93° at Verkhoyansk, in 67° 34′, near the river Lena. A great part of the Siberian coast is quite uninhabited, but some hardy tribes extend their wanderings to, and even have permanent settlements on the shores of the polar sea. The Samoyeds, with both reindeer and dog-sledges, extend their wanderings to the Yenisei. The Ostiaks of the Obi and upper Yenisei rivers, numbering 27,000, are Finnish and have close racial affinities with the Samoyeds. They possess a fine breed of dogs, but live chiefly by fishing. The Yuraks of the Yenisei are a branch of the Samoyeds. The Tunguses and Yakuts wander further to the east, as far as the Kolyma. The mysterious Onkilon or Omoki inhabited the river banks and sea shores of eastern Siberia. “Once there were more hearths of the Omoki on the shores of the Kolyma than there are stars in a clear sky.” They were established in fixed settlements. The remains of their forts, built of tree trunks, and their tumuli are found, especially near the banks of the river Indigirka. Nordenskiöld found the ruins of their house-sites near his winter quarters, and his excavating operations were rewarded by finding a stone chisel with a bone handle, slate knives, bone and slate spear-heads, and a bone spoon. Some centuries ago there was great pressure from the south, and the Onkilon, Omoki, and Chelagi appear to have been driven northwards. The Omoki are said to have gone away over the frozen ocean, but it is not known whither. It is thought that they went to the land said to be visible from Cape Jakan in clear summer weather. At all events they disappeared.