HOW MAN AND THE ANIMALS ARE AFFECTED BY THE WEATHER-CHANGES.

PERSONS subject to rheumatism frequently write to me relative to their barometric propensities, and did the limited space permit I could furnish many a laughable letter respecting the numerous indications of the weather given by the "twinges" of afflicted individuals. The fact is, that persons subject to rheumatism and like complaints become affected, probably upon hygrometric principles, when the atmosphere becomes damp, and feel relieved when dry weather returns. Such individuals may be considered living hygrometers.

What is a hygrometer? I know many of the readers of the Almanac will at once inquire. This instrument was briefly described in my Almanac for 1877-78 (page 97). The principle upon which it has been generally constructed is that a certain degree of affinity exists between moisture and air and moisture and many other substances-that one substance attracts another for which it has an affinity with proportionately less force according as it is more nearly saturated with it. Thus, a hair or piece of catgut may be used for hygrometric purposes, for either of these substances exerts a certain degree of attraction for moisture. Accordingly, as the air gets more nearly saturated, and exerts a proportionately less attractive force for humidity, these substances absorb a greater amount of moisture, and in so doing expand in thickness but diminish in length. On the other hand, when the air becomes drier than usual, and exerts a proportionately stronger attraction for moisture, a portion of humidity is abstracted from these bodies; and this, while it diminishes their thickness, increases their length. Hence the length of such or similar substances, fitted up and adjusted to a scale of equal parts according to various mechanical contrivances, has been employed as a measure of the dryness and dampness of the atmosphere.

Another principle upon which hygrometers have been constructed is based upon the different degrees of rapidity with which moisture evaporates and reduces the temperature of the evaporating surface, according to the state of the atmosphere as to humidity. As, however, I do not mean to describe meteorological instruments generally, this point need not be further enlarged upon. One object in remarking upon such instruments is, that if the principles of their construction be correctly understood a great mass of weather-indications held in esteem by the more

ignorant part of the population, and which depend upon the same principles, become intelligible.

man.

We have already referred to the effect of the changes of weather upon Birds, beasts, insects, and reptiles are similarly affected. These, by their peculiar cries and instinctive movements (which have always been considered indications of wet or dry weather), evince that they likewise are affected with agreeable or disagreeable sensations according to the nature of the change approaching. But, in truth, the animals themselves know nothing of the cause of such sensations, and, though they manifest their sensations by peculiar cries and other traits, possess no foreknowledge of the weather. When we consider that perspiration is more or less obstructed by increased dampness, and that the feathers of birds and the hair covering the skins of beasts, as well as the muscular fibres of animals in general, are all better or worse hygrometers, it is no wonder that variations in the dryness or dampness of the atmosphere should give rise to agreeable or disagreeable sensations.

PLUMAGE OF BIRDS.—The plumage of birds is composed of materials which are bad conductors of heat, and are so disposed as to contain in their interstices a great quantity of air, without leaving it space to circulate. For such species as inhabit the colder climates a still more effectual provision is made; for under the ordinary plumage, which is adapted to resist the wind and rain, a still finer and more delicate down is found, which intercepts the heat which would otherwise escape through the coarser plumage.

What the plumage does for the bird, wool for the animal, and clothing for the man, snow does in winter for the soil. The farmer and the gardener look with dismay at a hard and continued frost which is not preceded by a fall of snow. For the snow is nearly a non-conductor, and when sufficiently deep may be considered as absolutely so. The surface may therefore fall to a temperature greatly below 32°, but the bottom in contact with the vegetation of the soil does not share in this fall of temperature, remaining at 32°—a temperature at that season not incompatible with the vegetable organization. Thus the roots and young shoots are protected from a destructive cold.

DROUGHTS AND RAINS.-During long hot, dry terms of weather in medium latitudes, or at distances from the sea, the vapors are carried over or past them, and condensed in the more northern latitudes or farther from the ocean. Medium latitudes from the sea receive a fair share of rain in moderate seasons. During long cold intervals the vapors are in all likelihood condensed before reaching far north or inland from the ocean.

THE TERRIBLE SUMMER OF 1881.

UNEXAMPLED DROUGHT ON THIS CONTINENT.

IN America the drought has been most extended and beyond comparison most destructive. It commenced in April, and after increasing in intensity in some places and diminishing in others in early summer, it uniformly developed over most of the settled part of the United States and Canada in the end of July into a steady, persistent dry period, which, under a burning sun, withered the crops yet standing, burned the grass brown, baked the soil, dried up most of the rivulets, and made the tinderlike forests an easy prey to the great fires which overspread for weeks a territory of half a million square miles with a pall of smoke and ashes.

1,500,000 DRIED-UP MILES.

The limits of the drought are not precisely known, but the area may be roughly described as an immense oval extending from Central Texas in the south-west to a little beyond Montreal in the north-east, and from Kansas and Iowa to Georgia on a north-west and south-east line. This includes a territory 1600 miles long by over 900 miles wide, embracing nearly 1,500,000 square miles-eight times as large as France, or thirteen times as large as Great Britain and Ireland. In Georgia, and also in Virginia and other central parts of this area, the drought was intense for between three and four months, while generally elsewhere it was only in July, August, and September that the effects of the dry weather were at all marked.

A VERY HOT SUMMER.

The heat of July and August was, however, extremely great, and in fact the summer as a whole was warmer than usual. In New Orleans in July the thermometer rose to 100°, which was the highest temperature in New Orleans for several years. Similar temperatures were reached in Ontario both in that month and in August, while in September the mercury rose to 100.5° at Hamilton, Ontario, 104° at Washington, 100° at New York, and 105° in the backwoods of Ontario. Toronto, which rarely suffers from the intense heats known elsewhere in Canada, recorded a temperature of 93°. At the Meteorological Station in Brantford the average daily maximum in July was 88.9° in the shade, and in August 88.7°, while the thermometer exceeded 90° in the shade on seven days in May, twenty-one in July, sixteen in August, and on many days in September. From the 16th of July for twenty consecutive days the mercury reached from 90° to 99.5° in the shade. The following shows the mean temperature for May, June, July, and August at Toronto and Brantford :

September, up to the 25th, averaged in Toronto about 68°, and in part of South-western Ontario over 70°, while the highest temperatures equalled or surpassed those of July and August. In fact, no part of Europe and few parts of the tropics ever show higher temperatures than have been recorded in Ontario this summer.

RAINFALL IN ONTARIO AND NEW YORK.

The following tables show the rainfall for April, May, June, July, and August of this year at New York, Toronto, Brantford, Kingston, and Parry Sound, as well as the average for these months over a long series of years at New York and Toronto. The average for Toronto may be taken to be nearly the average of the three other Canadian towns:

It will be noticed that in April and August the drought was intense at all these places, and although Toronto shows as much as half the average rainfall, two-thirds of that fell on one day-the 2d of the month. May, June, and July differed much at different places, the excesses which seem to interfere with the continuity of dry weather being due to occasional and purely local thunder-storms, with heavy precipitation. The distribution of the days of rain makes the drought still more formidable, for, excluding the days on which a few scattering drops fell from the reluctant

skies, two or three was the total number of days on which rain fell sufficiently heavy to penetrate an inch into the ground. In Brantford on only one day in August did any rain whatever fall, and after the beginning of that month the drought was unbroken.

EXTRAORDINARY FIGURES.

At Kingston the rainfall in July and August amounted to only .88 of an inch, or about five inches below the average. This rainfall, under the burning sun of a Canadian summer, could not, if it fell at once, keep the ground damp for a single day, and, falling on several days, barely sufficed to lay the dust for a few hours at a time. The actual shortage in the supply of rain was five hundred tons per acre in that district of country, or a sufficient quantity, for a township ten miles square, to form a lake of four thousand acres that is, larger than Toronto Bay-and deep enough in any part to cover over head a man six and a half feet in height.

If the deficiency over the province at large be estimated at four inches for July and August, the deficiency in the Province of Ontario from Lake Nipissing southward would equal a lake forty miles long, twenty-five miles wide, and twenty feet deep.

In the Mississippi Valley, and over most of the United States affected by the drought, the rainfall is usually much greater than in Canada, and if the average deficiency for the four months be assumed to be only ten inches, the lack of rain on the area of 1,500,000 miles reaching from Texas to Montreal would equal the total area of Lakes Superior, Michigan, Huron, Erie, and Ontario, and several of the smaller lakes added, with an average depth throughout of fifteen feet, or sufficient to float the largest vessel that navigates the lakes. If gathered together with a depth of one hundred and twenty feet-the average depth of Lake Erie-a lake would be formed somewhat larger than that lake, which is two hundred and forty miles in length by from thirty to sixty broad.

Another comparison will suffice. The total deficiency over the area referred to was 1,100,000 cubic miles of water. Niagara Falls at floodheight, discharging at the rate of one million cubic feet of water per second, would require one whole year to pour this vast quantity of water over into the raging chasm below.

With so enormous a deficiency in the rainfall it is not to be wondered at that Lake Ontario has fallen rapidly during the past month, and, as may be seen at the island opposite Toronto, is now eighteen inches lower than for many years, if not lower than ever before recorded. The absence of a Lake Erie full of raindrops has dried up the springs of half a continent, narrowed broad rivers to lines of dark water flowing shallowly