Floating or swimming freely were examples of pteropods, worms, crustaceans, ostracods, and jelly-fish. These were easily taken in the hand-net.
In those regions where ice and water are intermingled, the temperature of the water varies very slightly in summer and winter, remaining approximately at freezing-point. In summer the tendency to heating is neutralized by a solution of some of the ice, and in winter the cold is absorbed in the production of a surface layer of ice. This constancy of the sea's temperature is favourable to organic life. On land there is a wide range in temperature, and only the meagre mosses and lichens, and the forms of insect life which live among them can exist, because they have developed the capacity of suspending animation during the winter. The fresh-water lakelets were found to be inhabited by low forms of life, mainly microscopic. Among these were diatoms, algae, protozoa, rotifera, and bacteria.
The last-named were investigated by McLean and were found to be manifold in distribution. Besides those from the intestines of animals and birds, cultures were successfully made from the following natural sources: lichen soil, moss soil, morainic mud, guano, ice and snow. The results may open some new problems in bacteriology.
Of recent years much attention has been given to the study of parasites—parasitology. Parasites may be external, on the skin; internal, in the alimentary canal; or resident, in the corpuscles of the blood. In tropical countries, where there is great promiscuity of life, one is led to expect their almost universal presence. But in polar regions, where infection and intimate co-habitation for long periods are not the rule, while the climate is not favourable to organic existence, one would be surprised to find them in any great number. The fact remains that internal parasites were found in the intestine of every animal and fish examined, and in all the birds except the Wilson petrel. External parasites were present on every species of bird and seal, though individuals were often free of them. This was so in the case of the Adelie penguins. It is a demonstration of the protective warmth of the feathers that Emperor penguins may harbour insect parasites in great numbers. It is only less wonderful than the fact that they are able to rear their young during the Antarctic winter. A large number of blood-slides were prepared and stained for examination for blood-parasites.
Searching for "fleas" amongst the feathers of birds and the hair of seals, or examining the viscera for "worms" is neither of them a pleasant occupation. To be really successful, the enthusiasm of the specialist is necessary. Hunter allowed no opportunities to pass and secured a fine collection of parasites.
Amongst other work, McLean carried out monthly observations on six men, determining the colour-index and haemoglobin value of their blood over a period of ten months. The results showed a distinct and upward rise above the normal.
Among societies privileged to see the daily paper and to whom diversity and change are as the breath of life, the weather is apt to be tabooed as a subject of conversation. But even the most versatile may suddenly find themselves stripped of ideas, ignominiously reduced to the obvious topic. To us, instead of being a mere prelude to more serious matters, or the last resort of a feeble intellect, it was the all-engrossing theme. The man with the latest hare-brained theory of the causation of the wind was accorded a full hearing. The lightning calculator who estimated the annual tonnage of drift-snow sweeping off Adelie Land was received as a futurist and thinker. Discussion was always free, and the subject was never thrashed out. Evidence on the great topic accumulated day by day and month by month; yet there was no one without an innate hope that winter would bring calm weather or that spring-time, at least, must be propitious.
Meanwhile the meteorologist accepted things as he found them, supplied the daily facts of wind-mileage and direction, amount of drift, temperature and so forth, which were immediately seized by more vivacious minds and made the basis of daring speculations.
The daily facts were increased by the construction of a new instrument known as the puffometer. It was entirely a home-made contrivance, designed to measure the speed of heavy gusts of wind. A small aluminium sphere was arranged to blow out at the end of a light cord exerting tension on a calibrated spring. The pull was transferred to a lever carrying a pencil, which travelled across a disk of carbonized paper. The disk, moving by clockwork, made a complete revolution every hour. The recording parts of the instrument were enclosed in a snow-proof box in which there was a small aperture on the leeward side, through which ran the cord attachment of the sphere. This may give a rough idea of the apparatus employed to measure the momentary velocity of the cyclonic gusts. The idea is not an original one, having been previously applied for use on kites.
It was not always possible to use the puffometer in the strongest gusts because these were often transient, occurring unexpectedly or during the night; while it took a little time to get the instrument into running order. Even in daylight, with the landscape clear of drift, it was a time-absorbing and difficult task to secure a record.