Sept. 5, 1889] 



NATURE 



449 



GEOGRAPHICAL NOTES. 



From advices just received from Queensland the Colonics and 

 India understands that Sir William MacGregor left Port Moresby, 

 for the ascent of Mount Owen Stanley, on April 19, in an open 

 boat, with a party of fourteen for Vanapa River, 30 miles west- 

 ward. He arrived safely, and pushed the boat up river for 

 eight days, during which period he encountered many difficulties 

 in crossing rapids and dragging the boat over rocks. When he 

 could get no lurther he camped on the left bank of the river and 

 sent Mr. Cameron (his secretary) back to Port Moresby for 

 supplies, with native carriers to cross the mountain. Mr. 

 Cameron returned with two boats loaded with provisions, thirty 

 natives, and six Polynesians. All being ready, on May 17 the 

 party, comprising forty-two men, left the camp, all packing, and 

 the Governor taking the heaviest load. There were only four 

 whites in the party. They crossed Mount Gleason at Eyton 

 Junction, and then shaped a course north-east by east. At a 

 height of 175 feet they crossed Mount Gunbar, next Mount 

 Kulwald. Mount Belford was crossed at the Joseph River, after 

 which they descended to the Goodwin Spur, and saw the first 

 native house at Goodwin's village, Mount Musgrave, where they 

 camped, the Governor going ahead with four Polynesians and 

 seven natives ; then ascended Mount Musgrave for over 7000 

 feet to Vanapa River and Mount Knutsford Range, over rough 

 country ; they followed a spur leading west. After three days' 

 march they descended the spur, and began the ascent of Mount 

 Owen Stanley on June 9, reaching the top on June 11 and 12, 

 returning to Mount Musgrave on June 16. All hands started 

 homewards and arrived at River Camp on June 22. They left 

 on June 23, visited a mountain village on June 24, and met the 

 steam launch from the Merrie England, which was searching for 

 the Governor's party, and took them in tow. They arrived at 

 Mana Mana on the 25th, and were taken on to Port Moresby, 

 where the party landed after two months, all well. The only 

 death that occurred was that of a native. The country traversed 

 was very mountainous, and no table-land was discovered. Of 

 the geological formation the country is mainly decomposed slate, 

 granite, and quartz, with no sign of gold. Specimens of rock 

 were collected by the Governor. The climate to 8000 feet is 

 moist, above that dry and bracing. Natives were met on only 

 two occasions, and were extremely friendly. They were stout 

 well-built men, but no women were ever seen. Cultivation 

 paddocks were fenced in. Potatoes, yams, and sugar-cane were 

 plentiful, as also was tobacco. Natives, who were devoid of 

 warlike implements, paid particular attention to head-dresses 

 made of shells procured from the natives on the eastern coast of 

 German New Guinea, who were showing friendly communication. 

 Across the Owen Stanley Range the Governor collected many 

 specimens of new plants, among others being some beautiful 

 yellow rhododendrons, which he has since sent to Melbourne to 

 Baron Von Mueller for report. A great number of new grasses 

 in large patches were discovered. At Mount Victoria (Goodwin) 

 he secured several new birds and one animal, which was some- 

 thing like a native bear, but had a long tail and dusty-brown 

 collar and black extremities. The extreme length was 3 feet 6 

 inches, of which the tail was i foot 6 inches. There were five 

 claws on all the feet, the tail was bushy, and it was estimated 

 that the weight of the animal was 40 pounds. The birds of the 

 lower altitudes were the same as those before seen, except as to a 



new paradise bird similar to the Great Epimachus. Sir William 

 procured a female Astrachia stcphania, the only male bird of 

 that species being in the Museum, Berlin. The Governor pro- 

 cured several new small birds at Mount Victoria, including the 

 identical English lark. Unfortunately, they were eaten by the 

 Polynesians. Entomological specimens were obtained, including 

 a milk butterfly. Only a few were captured. 



According to a limes telegram from Zanzibar, the Sultan 

 has signed a concession to the British East Africa Company, of 

 Lamu and the Ben-Adir coast, embracing all his territory from 

 Kipini to Mruti. The concession embraces the administration 

 and government of the island and port of Lamu, and of the 

 northern mainland ports of Kismayu, Brava, Magadisho, and 

 Warsheikh. The company's jurisdiction is thereby extended 

 from the River Umba, in the south, to the port of Warsheikh in 

 the north, an extent of about 700 miles of coast-line. Lamu is, 

 next to Zanzibar and Mombasa, the most important port on the 

 East African coast, and commands the trade of the mainland 

 south of Kismayu, and that of the fine waterway of the Tana. 

 It has been for years past the seat of a flourishing commerce, 

 which is mostly in the hands of British Indian subjects, and it is 

 a port of call for the British India Company's steamers. 



OUR SENSATIONS OF MOTION."^ 



XA/E may distinguish two quite different kinds of sensation of 

 motion, active and passive. When we walk or run or 

 row, we use our muscles, and this use of our muscles is the cause 

 of our motion, and also the cause of special sensations which 

 may in a sense be called active sensations of motion. But we 

 have other sensations than these connected with motion. For, if 

 we are carried, or rocked in a boat, or dropped from a height, 

 we are not only moved, but we are conscious of a very well marked 

 sensation which we may call a passive sensation of motion. 

 When we move ourselves we feel both kinds, and it is difficult 

 for us to analyze what we feel and distinguish between our sensa- 

 tions as movers and our sensations as moved. It is to our passive 

 sensations of motion that I wish to direct your attention to-night, 

 and as these can best be examined in cases where they are not 

 complicated with the other kind, we shall confine our attention 

 almost exclusively to passive motion — that is, to cases wh.re we 

 are moved without any exertion of our own muscles. Now the 

 first thing I have to say is in at all events apparent contradiction 

 to the title of this lecfure : it is that we have no direct sensation 

 of moiion as such. That this is so will be at once obvious if we 

 consider the fact known to all, that we are at this moment being 

 moved with very great velocity through space. W^e know that this 

 is so, astronomers can prove it, but we are so perfectly unconscious 

 of it that I dare say most of us here could not point the direction 

 in which we are moving; in fact, as we are ignorant of the direc- 

 tion and rate of motion of the great system of which our solar 

 system is a part, no one can say how fast and towards what point 

 in space we are travelling. What we are conscious of is change 

 of moiion. It is because the motion of the earth is so steady, 

 because, although very rapid, its changes are very slow, that we 

 do not feel it. 



There are two altogether different ways in which a body can 

 be moved. These have been called respectively translatory 

 and rotational. In translatory motion the body is always simi- 

 larly oriented. Thus, if we consider moiion within so small 

 a part of the earth's surface that we may neglect the earth's 

 curvature, such an object as this desk is subjected to purely 

 translatory motion if we move it thus, so that the same side 

 alw.ays looks up, and the same side always looks east. Rota- 

 tional motion involves a change of orientation, and is rotation 

 about an axis. This axis may always be the same, or it may 

 change, and the change of axis may be abrupt or may be con- 

 tinuous. Most of the motions which we observe are made up of 

 both kinds. When we travel by rail — always supposing that we 

 sit still in the carriage— we are subjected to a purely translatory 

 motion only when the train is running along a perfectly straight 

 piece of the line. When it goes round a curve, we are^ — always 

 supposing we sit still— subjected to rotation as well as to transla- 

 tion ; because our face no longer continues to look in the same 

 direction, but, as long as the train is running on the curve^ con- 

 tinuously changes the direction in which it looks. 



Let us examine what we feel when we are passively subjected 

 to purely translatory motion. As long as the motion is steady, 

 'Arjiitstead Lecture delivered in Dundee, by Prof. A. Crum Brown. 



