54 
NATURE 
[Vov. 17, 1881 
the names of distinguished men commanding naval expeditions, 
who themselves, or the officers under them, did a large amount 
of discovery and good scientific work, are mentioned, however 
briefly. Yet this is far from being the case. True, some of 
those expeditions which have been considered unworthy of 
notice were sent to the far north to gain tidings of the lost 
expedition under the good and noble but unfortunate Franklin ; 
yet, in addition to doing an immense extent of sledging, by 
which many hundred miles of wew coast were traced, they col- 
lected much scientific information, little, if any, less valuable 
than that brought home by the Nares Expedition, whose object 
was purely scientific. 
The names of Kellett, Belcher, and Austin are conspicuous 
by their absence, except a notice of the officer who acted as 
second to the latter, and who made a comparatively short sledge 
journey. We can scarcely suppose that the author was in any 
way influenced by the fact that he himself sailed in the same 
vessel under the immediate command of the officer whom he 
selects for notice, whilst wholly ignoring Admiral Austin, the 
chief in command. 
The names of the Americans, Kane and Hayes, who with 
very inferior means traced sore than 300 mes! of the unknown 
shores of Smith’s Sound, are left out, although each was 
awarded the gold medal of the Royal Geographical Society— 
the highest honour that can be bestowed on an explorer—for 
their Arctic discoveries, as being the most important of the year 
in which they were made. These are a few examples to prove 
what has been said. 
The author attempts to show that the system of sledging 
adopted by the Government Naval Expeditions is all but perfect, 
and that the first long sledge journeys were performed by them. 
Both these statements admit of question. The sledging arrange- 
ments are more or less defective in almost every particular. The 
tents are bad shelters, far inferior to snow-huts ; the sleeping- 
bags are objectionable, as they prevent transmission of caloric 
from one individual to the other. The bag itself, being exposed 
all day to a temperature of perhaps 20° or 30° below zero, is 
so cold when the occupant gets inside, that all the moisture from 
the breath, &c , gets condensed upon it, making this bed after a 
few days’ u e like ‘‘sheet iron” (as remarked by a naval officer 
who had some unpleasant experience of the fact) and afterwards, 
when thawed by the extraction of most of the animal heat from 
the shivering tenant, becomes a veritable ‘‘ wet blanket.” Be- 
sides this blanket bag each man before going to rest (?) struggled 
into what is called a ‘‘jumper” made of thick duffle, cold as 
the other night-gear, thrusting the arms into the sleeves, thus 
keeping these unfortunate members separated by two folds of 
a thick non-conductor from the body that owned them, a pro- 
cedure wholly opposed to both experience and science. To 
conserve the animal heat the Indian and white voyageur either take 
off their coats or take their arms out of the sleeves when camping 
out in winter. The Eskimo strips to the waist in his snow hut. 
It is only the naval Arctic sledge parties that act differently, with 
very uncomfortable results. The construction of the sledges is 
very defective for certain conditions of snow when in a semi- 
packed state—the sledge-runners then sink down six or seven 
inches, and have to be dragged with great difficulty ¢hrough the 
snow, not over it. The dead weight—exclusive of food and fuel 
—to be hauled on this ‘‘admirable system ” usually amounted to 
85 or go lbs. per man, which weight has been reduced under 
another system to 35 or 40 lbs. per man without loss of 
efficiency. 
““Long-sledge journeys,” which Mr. Markham claims to have 
been initiated by the Government Naval Expeditions, were 
made at the rate of twenty miles or more a day by civilians, 
before the ‘‘naval system” was put in use, the first occasion of 
which was by the most experienced of Arctic explorers, Sir 
James C. Ross, in 1849, when the results were by no means 
satisfactory, considering the large number of men employed ; a 
small party of five Hudson’s Bay men having accomplished more 
than double the distance at nearly double the daily rate two 
years before over very difficult ice. 
Mr. Markham ‘‘formulates three canons,” which, he says, 
‘fare equally important, as the true methods for future Polar 
research,” but the latter of these, namely, ‘to reach an ad- 
vanced position within the unknown area, it is necessary to 
follow a coast line trending northwards, with a western aspect, 1s 
of most interest to the geographical inquirer.” 
z * This distance (300 miles) of new discoveries is that credited to the Nares 
Expedition by Mr. Markham. 
The four words I wish to comment upon are in italics. Had 
not Mr. Markham given examples of his meaning by mentioning 
Foxe’s Channel and Regent’s Inlet, I should have supposed 
“western aspect” a misprint. 
It is a curious but certain fact, established by men who have 
been there, that the shores of all bays and inlets on the northern 
coast of America, the shores of all inlets and of the great 
islands lying north of America, having a westerns aspect, are 
usually ice-blocked, whilst the shores having an eastern aspect are 
comparatively free from ice and navigable. As cases in point 
Hudson’s Bay, Regent’s Inlet, Victoria Strait, the shores of 
Banks Land and Melvile Island, also Smith Sound,? are all far 
more ice-obstructed on the shores having a western than on those 
having an eastern aspect.” 
The greater frequency of westerly and north-westerly winds 
and gales in the western hemisphere in high latitudes are of them- 
selves sufficient to produce the effect I have mentioned, and to 
form the so-called ‘‘ancient ice” in a month or less. 
The route by the west shore of Franz-Josef Land is named as 
favourable for getting far to the north. This may be true, but 
from the formation of the land it may be considered as by no 
means safe. The most experienced navigators of these seas 
state that Franz-Josef Land may perhaps be reached once in 
every four or five years, as the condition of the ice in Barentz 
Sea is very uncertain. Supposing this to be true, might not 
the vessel that was fortunate enough to reach these interesting 
islands be detained there rather longer than was either safe or 
agreeable? Already some not unreasonable anxiety is felt for 
Mr. Leigh Smith in his fine vessel manned by able icemen, who, 
it is believed, sailed in the direction indicated. Fortunately he 
is in every respect well provided to face ove Arctic winter. 
That a large quantity of heavy ice is to be generally met with 
in the Sea of Barentz is not difficult to account for—S pitzbergen 
on the west, Franz-Josef Land on the north, and Novia Zemblia 
on the east, forma sort of cz/-de-sac, into which the floes appear 
to be drifted about by winds and currents in a most erratic 
manner. 
Mr. Markham states that the ‘‘ancient ice” $0 or 100 feet in 
thickness seen by Nares and other Arctic navigators is the result 
of “slow accretions,” meaning, I presume thereby, that these 
great ice-masses are the gradual growth of a single floe by the 
freezings of many winters. My opinion is that this thick-ribbed 
ice is the result of extreme pressure, which has forced one floe 
over or under the other, as in the case of the upheaval of the 
Austrian ship with Weyprecht and Payer in 1873-4, of which 
mention has already been made in the columns of NATURE, 
It is doubtful if the extremest cold of an Arctic winter would 
have any freezing influence on the lower surface of a floe 60 or 
80 feet thick, only 9 or 12 feet of which was above water, whilst 
the remaining 50 or 68 feet were submerged. The known effect 
of the action of the sea in wasting away the submerged portions 
of icebergs, even when these are not large, tends to support the 
theory I suggest. J. RAE 
4, Addison Gardens, W., November 5 
A Photographic Experiment with Swan’s Incandescent 
Light 
SoME trials I have recently made with Swan’s incandescent 
electric lamps give results that may possibly interest your 
readers. I employed throughout an electric stream of the 
same energy—that generated by thirty Grove cells, and as the 
whole experiment lasted but an hour, it may be assumed, for all 
practical purposes, that the strength of the current was uniform 
throughout. 
I made use of four lamps in all, supplied promiscuously from 
Newcastle, their resistances being respectively : No. 1, 67 ohms; 
No. 2, 59 ohms; No. 3, 58 ohms; No. 4,52 ohms. My object 
was to ascertain their actinic power upon a gelatino-bromide 
film, individually, collectively, and in groups. To do this I 
exposed a gelatino-bromide film to the action of one light at a 
distance of 14 feet, the sensitive film being placed behind a 
screen more or less transparent. The screen was divided into 
small squares, each representing different thicknesses of fine 
tissue paper. Thus: square marked No. 1 represented one thick- 
ness; No, 2, two thicknesses; No. 3, three thicknesses, and so on ; 
* The author says that Sir G. Nares ascended Smith Sound having a 
northern trending, but he does not tell us that both on the outward and 
homeward voyage he kept to the shore having an eastern asfect—a fact. 
2 The east coast of Greenland is an exception to this rule, being ice- 
encumbered by the force of a well known strong current pressing the floes 
against it. 
