10. During the summer Orel took soundings of the depth of the sea, which he was prevented from continuing in the winter by the frost. These show its shallowness on the north of Novaya Zemlya, especially towards Franz-Josef Land. A bank, over which we drifted in the summer of 1873, and which we explored with a drag-net, was the principal source of the collection of marine fauna, which we shall speak of in a later chapter. These soundings also enabled Orel to prove the small increase of the temperature of the sea at any considerable depth. He used in his experiments the maximum and minimum thermometer of Casella. The specimens we collected showed, that the bottom of the sea consists of layers of mud and shells. The soundings are exhibited in the following table:— +----------------+-------+ | Time. |Metres.| +----------------+-------+ | July 20 1872 | 400 | | ” 28 ” | 115 | | ” 31 ” | 250 | | Aug. 3 ” | 130 | | ” 4 ” | 80 | | ” 22 ” | 36 | | ” 30 ” | 170 | | Sept. 16 ” | 100 | | ” 25 ” | 90 | | ” 29 ” | 85 | | ” 30 ” | 190 | | Oct. 2 ” | 170 | | ” 9 ” | 450 | | Nov. 14 ” | 345 | | Jan. 28 1873 | 510 | | Mar. 27 ” | 450 | | April 28 ” | 350 | | May 17 ” | 230 | | ” 18 ” | 187 | | ” 19 ” | 172 | | ” 20 ” | 163 | | ” 21 ” | 138 | | ” 22 ” | 186 | | ” 23 ” | 162 | | ” 25 ” | 177 | | ” 25 ” | 182 | | ” 26 ” | 186 | | ” 27 ” | 249 | | ” 28 ” | 251 | | ” 29 ” | 254 | | ” 30 ” | 253 | | ” 31 ” | 256 | | June 1 ” | 238 | | ” 2 ” | 210 | | ” 3 ” | 183 | | ” 4 ” | 207 | | ” 5 ” | 200 | | ” 6 ” | 198 | | ” 7 ” | 190 | | ” 8 ” | 215 | | ” 9 ” | 231 | | ” 10 ” | 203 | | ” 11 ” | 240 | | ” 12 ” | 218 | | ” 13 ” | 211 | | ” 14 ” | 235 | | ” 15 ” | 161 | | ” 16 ” | 184 | | ” 17 ” | 222 | | ” 18 ” | 200 | | ” 19 ” | 186 | | ” 20 ” | 220 | | ” 21 ” | 195 | | ” 22 ” | 200 | | ” 23 ” | 169 | | ” 24 ” | 178 | | ” 25 ” | 195 | | ” 26 ” | 220 | | ” 27 ” | 227 | | ” 28 ” | 233 | | ” 29 ” | 240 | | ” 30 ” | 240 | | July 1 ” | 240 | | ” 3 ” | 245 | | ” 4 ” | 250 | | ” 5 ” | 235 | | ” 6 ” | 235 | | ” 7 ” | 274 | | ” 8 ” | 266 | | ” 9 ” | 250 | | ” 10 ” | 250 | | ” 11 ” | 236 | | ” 12 ” | 265 |