Page:The New International Encyclopædia 1st ed. v. 19.djvu/144

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TEMPERANCE. 116 TEMPERATURE VARIETIES. 000 members have been on the rolls since the organization of the order. The ritual is very im- pressive. The order is now established in Great Britain, Ireland, the Bahamas, Liberia, New Zealand. Australia, Scotland and Wales. TEMPERATURE. See Heat. TEMPERATURE, Terkesthial. The distri- bution of heat in the atmosphere depends to some extent on its direct absorption of solar radiations, and especially the absorption at the upper surface of the clouds, but is principally governed by the angular altitude of the sun and the contact of the air v/ith the ground and the ocean. The numerous irregularities give rise to the great currents of air as well as to the local winds, and the latter carry the heat and the temperature rapidly from one part of the globe to the other, so that ultimately the atmospheric temperature is almost equally controlled by the winds on the one hand and the oceans, continents, rain, snow, and cloud on the other. The typical continental climates experi- ence great diurnal and annual ranges of tem- perature, and the typical oceanic climates show a small range. The distribution of temperature on any level surface at any depth below or height above sea level is shown by means of isotherms, which are drawn through all places that have the same temperature at any moment, or the same month- ly or annual mean temperature. Charts show- ing these isotherms have been published by vari- ous meteorological services for the air and the land, and by various hj'drographic offices for the oceans. The highest mean annual temperatures occur within the tropics and especially over the land areas of Northern Africa and Southern Asia, with corresponding small regions in Cen- tral America and the northern portion of South America. The lowest mean annual temperatures are found in Northern Siberia and the northern portions of British America, which represent the southern extension of a large Arctic area of low temperature. See Climate. TEMPERATURE OF THE BODY. The temperature in the healthy human adult aver- ages from 98.4° to 98.6° F., but 97.5° and 99° r. are within normal limits. In the new-born child the temperature is slightly above the aver- age, as it is in old age. Race has but a slight inlluence, a difference of .29° P. being observed between the nations of Southern Europe and those of the northern part. The temperature rises slightly after a meal and during exercise. During the day the body heat varies about half a degree, being highest between 5 and 8 P.M. and lowest between 2 and 6 a.m. In childhood the temperature is easily and rapidly influenced, slight ailments causing marked febrile reaction. The temperature is registered by means of the clinical thermometer, which is self-registering, placed in tlie mouth, axilla, fold of the groin, the rectum, or the vagina. The surf.ace of the body is slightly cooler than the interior. A temperature below 93° or above 108° F. is almost always fatal. The usual range in fevers is between 99.5° and 105° or 108° F. As a rule there is a constant relation between the amount of fever and the rapidity of the pulse (q.v.) in many people. A pulse of 80 indicates a temperature of 100° F. ; a pulse of 90, a temperature of 101° F., etc. A rise of temperature between 99° and 102° F. is termed slight or moderate pyrexia; from 101° to 105° severe pyrexia ; and above this point hj'per- pyrexia. Many chronic and a few acute diseases are characterized by a subnormal temperature. This is observed in hemorrhage, starvation, and wasting from chronic diseases. In the melan- cholia of certain mental troubles there may be great depression both of the general and sur- face heat. An elevation of temperature attends by far the greater number of diseases. In the great class of the acute general infections (see NosoLOCiY) an elevation of the body heat is the most important symptom and is proportional to the severity of the disease. Very marked ele- vation of temperature (hyperpj'rexia) is seen in tetanus, acute rheumatism, pernicious malarial fever, and after injuries to the spinal cord. In tetanus the thermometer may register as high as 112.5° F. In sunstroke or heat-stroke, an equally high point has been reached. Lastly, the temperature may rise just before death, and after it, in rigor mortis. See Animal Heat; Fever; etc TEMPERATURE VARIETIES. Varieties, races, or sub-species are largely differentiated by variation resulting from being subjected to dif- ferent influences, principally in the nature of temperature and comparative moisture. It is a matter of universal observation that widespread species present a great range of variability in size, proportion of parts, color and other char- acteristics, so that it is often a matter of doubt whether a variant ought to be classed as a geographical sub-species, or as a di.stinet species. When it appears that the same kind of variation affects all or nearly all of the animals of a certain class in a region, coincidently with the character of the local climate, it is fair to a.s- sume that the change from the normal noted is due to local climatic influence. Temperature seems to act most directly in producing the common form of seasonal dimorphism, which affects most of the higher animals that dwell in the temperate zones, and are called upon to en- dure the cold of winter as well as the heat of summer. This causes a semi-annual change in mammals and birds from a comparatively thin and short coat of hair or feathers in the warm half of the year to ii thicker and longer cover- ing more suitable to the cold season. In ad- dition to this there is always a greater or less change of color, the bright dress of summer, as- svimed after the spring molt, falling out in the autumn and being gradually succeeded by a plainer, less conspicuous suit for the winter months. The difference is often very great ; and in the arctic regions amounts to a change from decided colors in summer to pure white in win- ter. The comparative degree of average moisture in the air of two regions will be reflected in the colors and other features of the same species of animals inhabiting them ; those of the moist region xill have darker colors, and a tendency to larger size and proportionally longer ex- ternal parts, as bills, legs, and tails, than the dry land species, which will be more pale in color and compact in form. Dr. J. A. Allen has shown this very conclusivelv in his investigations upon North American birds. Let one of these