Jan. lo, 1884] 



NATURE 



247 



THE ENGLISH CIRCUM POLAR EXPEDITION^ 



ON April 14, 1882, I was informed tliat I was appointed to 

 the command of the Circumpolar Expediiion. I at once 

 proceeded to London, and was occupied until the day of sailing 

 in ijractice with the magnetic instruments at the Kew Observa- 

 tory, and the purchase of stores, &c., for the ex; edition. 



On May i Sergeant F. W. Co >k.sley, Royal Horse Artillery, 

 and Gunner C. S. Wedenby, Koyal Artillery, and on May 6 

 Sergeant Instnic or of Gunnery J. English, R.H.A., reported 

 themselves to me, and commen;ed attendance at Kew for 

 in^truction. 



Journey to Fort Rae.—We sailed from Liverpool on May II, 

 and arrived at Quebec on the 23rd. Here I spent some days, 

 finding that the steamer for the north did not leave Winnipeg 

 till June 10, and my party was very kindly afforded quarters m 

 ihecitadel by Lieut. -Col. Cotton, commanding the Canadian 

 Artillery at that p'ace. 



Having obtained a free ) ass for our baggage on the Grand 

 Trunk Railway, I ^tarted at once for Winnipeg, proceeding by 

 the lakes, that being the cheaper route, and the one which, on 

 the whole, exposed the instruments to the least knocking abont. 

 We reached Winnipeg on June 9, and left on the following 

 day by the Saskalcheivait steamer. On June 26 we reached 

 Carlton, where it was necessary to enga,'e carts to take our 

 baggage to Green Lake, a distance of 140 miles. 



On the 29th th - carts w ere taken across the river, and on the 

 30th we started for Green Lake, which Me reached on July 9, 

 having been delayed by the extreme badne>s of the road. The 

 heat of the weather aLo rendered a long halt necessary in the 

 middle of the day, and the flies 1 revented our animals from 

 feeding properly, incapacitating them for long marches or fast 

 work, and on one occision forcing us to halt for a whole day, 

 the oxen being so worried by them as to be ui.able to march. 



At Green Lake we entered upon the system of water commu- 

 nication that forms the only roadway in the north, and by way 

 of Portage la Loche, and the Clearwater and Athabasca River-, 

 we reached Fort Chipewyan on July 30. Here we had to await 

 the Mackenzie Kiver boats, there being no other means of 

 reaching Fort Rae, and it was not until August 17 that we were 

 able to start on this hst stage of our journey. We reache I 

 Great Slave Lake on the 22nd, on the evening of which day a 

 gale arose which stove in and sunk our boat, damaiing most of 

 our provi>iins. Fortunately we were able to repair the boat, 

 but it was not until the 2'5th that the weather allowed us to 

 proceed, and on the 27th we were again detained by a fresh 

 storm, so that it was not until 10 p.m., on August 30, that we 

 arrived at Fort Rae. 



Fort AV-.— Fort Rae i^ situated in lat. 62° 38' 52" N., and 

 long. 115° 43' 50" \V., at the south-west extremi'y of a peninsula 

 that juts out from the north-east shore of a long gulf running in 

 a north-westerly direction for more than 100 u iles from the 

 northern shore of the Great Slave Lake. It is almost entirely 

 surrounded by water, as shown in the annexed plan. The for- 

 mation is limestone. The land rises to a height of some 

 200 feet, and it is covered in part with mos-, in part with pines 

 and scanty bru-hwood. A few vegetables are grown in the 

 summer in ihe garden attached t > the Roman Catholic Mission, 

 bat for food the inhabitants chiefly depend upon the produce of 

 the nets, and on deer, which are brought in by the Indian 

 hunters attached to the post. 



On arriv.il it was found that the magnetic instruments required 

 a good deal of jetting to rights, their boxes being filled with 

 water and the fittings loosened, so that not a single in-lrument 

 was quite in working order. There was, moreover, no building 

 ready for their reception, so that it was not possible to keep 

 August 31— September I, as a term day, but we succeeded in 

 getting the meteorological instruments in position so as to 

 commence obseivalions with them at midnight on the 31st. 



We were fortunate in finding a building that admitted of con- 

 version into a magnetic observatory, it only requiring a floor, 

 fireplace, door, and windows to be habitable. This work was 

 at once commenced, and on September 3 the declinometer, on 

 the 4ih the bifilar, and on the 6th the vertical force magnetometer 

 were mounted in their places. This observatory was finished 

 on September 10, and anoher one commenced for a^troiiomical 

 and absolute magnetic observations, the continual «dnd rendering 

 out-door observations unsatisfactory. 



> " Rep irt on the Circumpolar Exped.t on to Fort Rae," by Capt. H. P. 

 Dawson, R.A. Communicated t-j the Royal Society by Prof. G. G. Stokes, 

 Sec.R.S. 



The men of my party were accommodated in the house of one 

 of the sub-officers of the fort, and I had a room in the house of 

 the Hudson's Bay Company's officer in charge. 



The in-trumen's, on the whole, suffered but little from tho 

 journey. One barometer and one thermometer were broken, 

 and the object glasses of the telescopes of most of the magnetic 

 instrmients were nearly opaque, the cement joining the two 

 lenses having, from som'e ciuse or o'her, melted on the journey. 

 Our provisions were more damaged, 190 lb-, of sugar, 30 lbs. of 

 tea, all our rice, and most of our baking powder having been 

 destroyed. 



The oberva'. ions were then carried on without interruption 

 until August 31, 18S3. 



Ma^iielic Obsetvatioiis. — The balance magneto ojeter was the 

 only magnetic instrument whose performance was not s.atisfactory, 

 as not only did it frequently get out of adjustment, but in times of 

 mr.gnetic disturbance it o'ten vi .rated through so large an arc 

 that exact reading was impossible. The other instruments were 

 remarkably free from vibration, and there was never any difh- 

 culty in reading them, but it was found necessary to extend the 

 scale of the biiilar on the side of decreasing force, owing lo the 

 great movements of this instrument. 



The greatest magnetic disturbance was 0,1 November 17, 18, 

 and 19, 18S2, when all the instruments moved at times beyond 

 the limits of their sca'es. On the first of these days the differ- 

 ence between the extreme easterly and westerly positions of the 

 declinometer magnet exceeded 10°. 



Aurora. — Aurora was ol>served on almost every clear night, 

 and was usually attended by more or less magnetic disturbance. 

 It did not appear to me, however, that the two phenomena stood 

 in the relation of cause and effect, but rather that they were both 

 due to a common cause. The most marked instance of connec- 

 t.on between the t^o phenomena consisted in a rapid decrease 

 in both vertical and horizontal magnetic forces which attended a 

 sudden outburst of aurora in the zenith. This was observed on 

 several occasi ms. The bifilar almost always showed a reduction 

 of horizontal force during a display of aurora. I al-o think that 

 the declinometer magnet tended to point towaids the brightest 

 part of the aurora, but that [sic) I have not yet had time to make 

 that careful comparison of the auroral and magnetic observations 

 which will be required to decide this point. It was found im- 

 po.sible to obtain pholo.Ljraphs either of the aurora or of its 

 spectrum-— the latter invariably presented the characteristic yel- 

 lowish gi-een line, and occasionally, but rarely, several other 

 bright lines were visible for a few moments towards the violet 

 ei-.dof the spectrum, and once a bright band was seen in the 



l' was also unsuccessful in my attempts to measure the height 

 of the aurora, chiefly from the want of a well defined point to 

 measure to, al-o from the fact that some hours were required to 

 prepare for this observation, whereas the appearance of a suit- 

 able aurora could not be predicted, and was, in fact, not of 

 frequent occurrence, and then often only lasting a few seconds. 

 For this observation two stations some miles apart should be 

 connected by telegraph and occupied for many days, or even 

 week-, in succession. 



Although I laid attention to the point, I never heard any 

 sound from the aurora save on the occa ion mentioned in a 

 former memorandum, but I made many inquiries on the subject 

 from residents in the country, both English and French, and 

 their statements agree so well, b ,th with one another and with 

 what 1 myself heard, that I am forced to conclude that the 

 aurora is at times audible, and that on these occasions it appears 

 to b , and probably is, very near ihe earth. 



Meteorological Obseri'aticvs.—Wnh. regard to the meteorological 

 observations, the station was somewhat unfavourably placed for 

 observations of wind, on account of the hill to the north-east, 

 but as w inds from this quarter were rare, the effect on the re- 

 sults will not be great, especially as one of the anemometers was 

 on an island in the lake, in an enti'-ely open situation. ^ 



The anemometers did not work quite satisfactorily, bemg at 

 times choked by ice ; but I hope by the comparison of the two 

 satisfactory results may be attained. 



The wind was usually either south-east or north-west ; and 

 when it blew from the fomier quarter, the motion of the U]oper 

 clouds often showed the existence of a north-westerly current. 



The hair hygrometers were found to be useless out of doors in 

 cold weather, on account of the formation of ice on the hair. 



The earth thermometers were read every alternate day : the 

 observations were interrupted by a carcajou, or other animal. 



