i i CRUISE OF STEAMER CORWIN IN THE ARCTIC OCEAN. 
our winter clothing. In striking opposition to this was the uncomfortably murky temperature of 
July 21, when the thermometer registered 45°, While the above is true of the weather in the more 
northern part of the Arctic, we found it in Kotzebue Sound, later in the season, much milder than 
it was at a corresponding date of the previous year. In the latter part of June at Saint Michael's 
we found the sun almost overpowering, although the thermometer registered but 60°. Why this 
incongruity should exist between the sensation of heat as experienced by the human body and the 
actual temperature as revealed by the thermometer, we are not prepared to say. All that we know 
from writers on the subject is that the sensations of heat and cold are relative and not absolute. 
In different latitudes, among the Andes in Peru, fur instance, the opposite condition is often 
noticed, a disagreeable sensation of cold not indicated by the thermometer being one of the 
experiences of travelers in that part of the world: the cold is keen and penetrating with the 
thermometer standing at but 60°. An excellent distinction is that which mentions these 
phenomena as physical cold and physiological cold; the former indicating that revealed by the 
thermometer, the latter that not indicated by instruments. 
Many Arctic travellers have noticed this relative sensation of cold as well as the impunity, and 
even a certain degree of comfort, with which they can expose themselves to a low temperature, 
whieh would be attended by serious results in a more southern clime. Dr. Hayes relates that in 
Greenland he went swimming in a pool of water on the top of an iceberg, and the captain of a New 
Bedford whaler has frequently gone swimming off the coast of Siberia. Taking advantage of 
one of these physiologically warm days, I took a plunge into the icy Arctie water, with no such 
motive, however, as that of Leander, nor did I, like Byron, have the ague after it; on the contrary, 
a swim of no great discomfort was followed by a pleasurable reaction. 
The actual rise of temperature that follows upon stripping in a cold atmosphere or upon first 
entering into a cold bath, is not one of the least curious phenomena of the regulative function of the 
pyrogenetic mechanism. Nor is the busy activity of the metabolic tissues and the metabolism of 
the food within the alimentary canal, which accounts for the source of the heat of such homother- 
mous animals as whales, seals, walrus, and the pygopodous birds, a subject to be passed by 
unmentioned. By what physical and chemical laws can we explain this morphological process— 
this physiological action of the protoplasm resulting in the evolution of kinetic energy sufficient to 
supply bodily heat to such animals as the seal and the whale, and enable them by remarkable 
adaptability to withstand the extreme cold of the Arctic? Does the rete miribilia of the whale and 
of the duck enable them to combine a greater quantity of oxygen with hemoglobin and thereby 
act as a source of heat, or is the function of the liver the chief thermogenic source? By what 
ineans does the energy-yielding material become changed into actual energy? Does the nervous 
system, acting as a liberating force like the throttle-valve in a steam-engine, remove hinderances 
or impediments to the conversion of potential into kinetic energy, or do all the internal work of 
the animal organism, all the mechanical labor of the internal muscular mechanism, with their 
accompanying frictions, and the molecular labor of the nervous and other tissues produce a 
certain amount of heat, and thus account for the special function of calorifieation ? 
The foregoing physiological queries, with many others, suggested themselves on hearing the 
statements of whalemen and walrus hunters with reference to the scalding sensation produced 
by the spurting blood while handling the bodies of recently killed animals, and it occurred to 
me that a series of thermometric observations, something after the manner of the experiments 
of Dr. Kidder in connection with the Fish Commission, but having for their object the investigation 
of the manifestation of animal heat by the marine mammaiia, would prove interesting and supply a 
scientific desideratum in addition to their novelty. 
While ample opportunities occurred to make these experiments, yet it is to be regretted that the 
only available instrument, a clinical thermometer, was unfortunately broken early in the season, 
The experiments were, to say the least, so rough and inconclusive that any record of them would 
be of questionable value. 
Another question in connection with the Arctic cold is, whether a sojourn in this region does not 
render one more susceptible to colds and disorders of the respiratory organs on returning to more 
temperate latitudes. The history of Eskimo who have spent avy time in our comparatively moder- 
ate climate shows how they have suffered in this respect, and colds have been known to prevail 
