FROST. 



aftnuals. The oak and ash are constantly 

 the latest in pushing their leaves ; the 

 greatest number unfold them in spring ; 

 the mosses and firs in winter. These 

 Striking differences, with respect to so ca- 

 pital a circumstance in plants as that of 

 unfolding their leaves, seem to indicate 

 that each species of plant has a tempera- 

 ture proper or peculiar to itself, and re- 

 quires a certain degree of heat to extri- 

 cate the leaves from their buds, and pro- 

 duce the appearance in question. This 

 temperature, however, is not so constant, 

 as, to a superficial observer, it may appear 

 to be. Among plants of the same spe- 

 cies, there are some more early than 

 others; whether that circumstanue de- 

 pends, as it most commonly does, on the 

 nature of the plants, or is owing to differ- 

 ences in heat, exposure, and soil. In ge- 

 neral, it may be affirmed, that small and 

 young 1 trees are always earlier than larger 

 or old ones. See GERMISTATIOK, and 

 Milne's Bot. Diet. 



FROST, such a state of the atmosphere 

 as causes the congelation or freezing of 

 water or other fluids into ice. In the 

 more northern parts of the world, even 

 solid bodies are affected by frost, though 

 this is only or chiefly in consequence of 

 the moisture they contain, which being 

 frozen into ice, and so expanding as water 

 is known to do when frozen, it bursts, and 

 rends any thing" in which it is contained, 

 as plants, trees, stones, and large rocks. 

 Many fluids expand by frost, as water, 

 which expands about one-tenth part, for 

 which i-eason ice floats in water ; but 

 others again contract, as quicksilver, and 

 thence frozen quicksilver sinks in the 

 fluid metal. 



Frost, being derived from the atmos- 

 phere, naturally proceeds from the upper 

 parts of bodies downwards, as the water 

 and the earth : so, the longer a frost is 

 continued, the thicker the ice becomes 

 upon the water in ponds, and the deeper 

 into the earth the ground is frozen. In 

 about 16 or 17 days frost, Mr. Boyle found 

 it had penetrated 14 inches into the 

 ground. At Moscow, in a hard season, 

 the frost will penetrate two feet deep into 

 the ground : and Captain James found it 

 penetrated 10 feet deep in Charlton 

 Island, and the water in the same island 

 was frozen to the depth of six feet. Shef- 

 fer assures us, that in Sweden the frost 

 pierces two cubits, or Swedish ells, into 

 the earth, and turns what moisture is 

 found thereinto a whitish substance, like 

 ice ; and standing water to three ells or 

 more. The same author also mentions 

 sudden cracks or rifts in the ice of the 



lakes of Sweden, nine or ten feet deep, 

 and many leagues long ; the rupture being 

 made with a noise not less loud than if 

 many guns were discharged together. By 

 such means, however, the fishes are fur- 

 nished with air ; so that they are rarely 

 found dead. 



The natural history of frosts furnish ve- 

 ry extraordinary effects. The trees are 

 often scorched and burnt up, as with the 

 most excessive heat, in consequence of 

 the separation of water from the air, 

 which is therefore very drying In the 

 great frost in 1683, the trunks of oak, ash, 

 walnut, &c. were miserably split and cleft, 

 so that they might be seen through, and 

 the cracks often attended with dreadful 

 noises like the explosion of fire-arms. Phl- 

 los. Trans. Number 165. 



The close of the year 1708, and the be- 

 ginning of 1709, were remarkable, 

 throughout the greatest part of Europe, 

 for a severe frost. Dr. Derham says it 

 was the greatest in degree, if not the niost 

 universal, in the memory of man ; ex- 

 tending through most parts of Europe, 

 though scarcely felt in Scotland or Ire- 

 land. 



In very cold countries, meat may be 

 preserved by the frost six or seven 

 months, and prove tolerably good eating. 

 See Captain Middleton's observations 

 made in Hudson's Bay, in the Philos. 

 Trans. Number 465, sect. 2. 



In that climate the frost seems never 

 out of the ground, it having been found 

 hard frozen in the two summer months. 

 Brandy and spirit, set out in the open air. 

 freeze to solid ice in three or four hours. 



Lakes and standing waters, not above 

 10 or 12 feet deep, are frozen to the 

 ground in winter, and all their fish perish. 

 But in rivers, where the current of the tide 

 is strong, the ice does not reach so deep, 

 and the fish are preserved. Id. ib. 



Some remarkable instances of frost in 

 Europe, and chiefly in England, are re- 

 corded as below ; in the year 



220 Frost in Britain that lasted five 



months. 



250 The Thames frozen nine weeks. 

 291 Most rivers in Britain frozen six 



weeks. 

 359 Severe frost in Scotland for 14 



weeks. 

 508 The rivers in Britain frozen for 



two months. 



558 The Danube quite frozen over. 

 695 Thames frozen six weeks; booths 



built on it. 

 759 Frost from Oct. 1, till Feb. 26, 



760. 



