Page:The American Cyclopædia (1879) Volume VII.djvu/308

 300 FOG FOGGIA fogs that occur, consists in this, that the moist air radiates its heat downward to a compara- tively cold body of either water, earth, or air. The former case occurs when the earth, after a period of low temperature, becomes quite cold, and the winds then waft warm moist air over the cold regions, while the small con- ducting power of the earth, ice, or snow does not allow its surface at once to follow the change in temperature. Fogs of the second class occur only during very clear nights ; the radiation from the earth then takes place with great freedom, and the moist air by this means coming into contact with the cold earth be- comes greatly reduced in temperature, and after depositing a heavy dew lies still in the valleys over the whole surface of the ground. To this body of cold air the superincumbent atmosphere radiates heat as freely as to the outer regions of the air, and even more rapid- ly because of its nearness. When by this pro- cess the temperature is reduced to the dew point, the aqueous vapor begins to condense as fog, the particles of which attach them- selves to neighboring solid bodies, such as leaves and branches of trees, but in a manner slightly different from the formation of dew. The third class of fogs, that produced by the radiation of atmospheric heat to a body of cold water, may occur in two ways: either warm air may be wafted ove"r bodies of cold water, or currents of cold water, may under- run bodies of warm moist air. The fogs on the coasts of New England, Nova Scotia, and Newfoundland, and those of the Gulf stream, belong in great measure to the former class, as the motion of the cold ocean currents must be considered quite slight in comparison with the rapidly moving winds. To the latter class belong fogs over rivers whose cold waters are flowing rapidly toward warmer regions. These are important features of the lower portions of the Mississippi, and have been well studied by Dr. W. M. Carpenter. (See "American Journal of Science " for 1843.) Concerning the exact condition of the vapor when in the state that constitutes a fog, much has been written since the first announcement by Kratz- enstein of his theory of the existence of fog vesicles as distinct from rain or dew drops. Notwithstanding the labors of Kamtz (1836), Meissner (1867), Muhry (1873), and others, it must be admitted that this theory is still sup- ported by too few minutely accurate observa- tions to allow its unqualified adoption ; and it is safer to presume that the particles of a fog are maintained floating in the air simply by the resistance offered by the atmosphere to the fall of minute spherical bodies. The dry fog that constitutes a characteristic feature of the North American Indian summer is not essen- tially different from the moor smoke (Moor- raucJi) of Europe, and has been satisfactorily traced to the burning of extensive tracts of forest and prairie land. From such fires the diluted smoke spreads with the winds over im- mense areas. The progress of these masses of smoke in the United States and Canada has of late years been very closely followed by the officers of the weather bureau of the army signal office, who have frequently been able to predict this phenomenon. The great fires of 1871 in the northwest, and indeed throughout the whole country, gave rise to remarkable exhibitions of this haze. An extraordinary dry fog is recorded to have covered the whole of Europe in 1783 for nearly two months. FOGELBERG, Bengt Erland, a Swedish sculp- tor, born at Gothenburg about 1787, died in Trieste, Dec. 21, 1854. He was the son of a bronze founder, studied in Stockholm and Paris, and spent upward of 30 years in Eome, taking rank next to Thorwaldsen. The sub- jects of his most celebrated works are from Greek and Scandinavian mythology, many of which are in the museum and in the private galleries of Stockholm. He also made bronze statues of Gustavus Adolphus and Charles XIY. (Bernadotte). FOGARAS, a market town of Transylvania, capital of a district of the same name, on the left bank of the Aluta, 32 m. W. N. W. of Kron- stadt; pop. in 1867, 4,714. It has a strongly fortified castle, built at the beginning of the 14th century and restored in the early part of the 17th by Bethlen Gabor. Fogaras gives title to the United Greek archbishop of the Roumans in the lands of the Hungarian crown ; but his residence is at Blasendorf. On July 12, 1849, Bern was defeated here by the Russian generals Engelhardt and Ltiders. FOGGIA. I. Also called CAPITANATA, a prov- ince of southern Italy, bounded N. and E. by the Adriatic, and bordering on the provinces of Bari, Potenza, Avellino, and Campobasso ; area, 2,955 sq. m. ; pop. in 1872, 319,164. It comprises the three districts of Bovino, Fog- gia, and San Severe. The Gargano peninsula forms in the southern part the gulf of Man- fredonia, on which opens the vast plain of Foggia. The Gargano range extends over 800 sq. m. on the S. E. side of the province, and the branches of the main Apennines rise on the S. W. Between the barren mountainous regions are exceedingly fertile valleys. The chief rivers are the Ofanto, Fortore, Candela- ro, Cervaro, and Carapella. The vine and the olive are extensively cultivated, and among the other products are grain, tobacco, licorice, hemp, and flax. The breeding of cattle, par- ticularly of sheep, is extensively pursued. II. A city, capital of the province, in the plain of Apulia (La Puglia), 80 m. N. E. of Na- ples, connected by rail with Ancona, Naples, and Bari; pop. in 1872, 38,138. It is well built, with wide clean streets, handsome houses and gateways, but no walls. It has about 20 churches, a cathedral originally Gothic, but rebuilt in a different style after its partial de- struction by an earthquake in 1731, several antiquities, a public library, and a theatre. The main streets and public squares are under-