CINQUE-FOIL 



runners resemble those of the strawberry. 

 This common kind of cinque-foil in the Middle 

 and Northern States is frequent in worn-out 

 and neglected fields, and, where abundant, indi- 

 cates thriftless farming. The Latin name of 

 the genus is derived from potens, powerful; 

 in reference to the supposed medical virtues 

 of the cinque-foil family. Another species, 

 commonly called five-fingers (Potentilla sim- 

 plex), is also a very common, yellow flowered 

 perennial, along the borders of woods, &c. 



CINQUE-FOIL, PURPLE MARSH (Coma- 

 riwn pahstre'). A perennial, found in spongy, 

 muddy bogs and ditches. Root, creeping ex- 

 tensively, with many long fibres. Stems, round, 

 reddish, a foot or more in height. Flowers, 

 several, without scent, but handsome, an inch 

 broad, all over of a dark purplish blood colour, 

 as well as the fruit. They appear in June. 

 (Smith's Eng. Flora, vol. ii. p. 433.) 



CITRIC ACIDS. Acids contained in le- 

 mons and some other kinds of fruit. See 

 ACIDS, VEGETABLE. 



CLARY, or SAGE (Sa/trio). Smith (Eng. 

 Flora, vol. i. p. 34) describes two kinds, the 

 meadow clary (S.pratensis), and wild English 

 clary (S. verbenaca). The first is very uncom- 

 mon, but sometimes met with in dry meadows 

 and about hedges ; grows three feet high, erect; 

 not very aromatic; leaves, dark-green; flowers, 

 large and handsome, of a fine purplish blue. 

 The second species is more common on gra- 

 velly or chalky soils, a foot or eighteen inches 

 high ; leaves, grayish-green ; flowers, small, 

 violet-blue. Seeds, black, smooth; blows from 

 June to October. This plant is of great vir- 

 tue, and is kept in gardens on account of its 

 excellent flavour. The whole herb is medi- 

 cinal, and is equally good, freshly gathered, 

 or dried. It is cordial and astringent in its 

 quality. 



CLASPERS. The threads or tendrils of 

 creeping plants. 



CLASS, an appellation used to denote the 

 most general divisions of which any thing is 

 susceptible. Thus in the Linnsean system of 

 natural history, the animal kingdom is divided 

 into six great classes, of mammalia, or ani- 

 mals which suckle their young; aves, or birds; 

 pisces, or fishes ; insecla, or insects ; vermes, or 

 worms. 



In botany, the term class implies the primary 

 division of plants into large groups, each of 

 which is to be subdivided by a regular down- 

 ward progression, into orders, genera, and spe- 

 cies, with occasional intermediate subdivisions, 

 constituting varieties, &c., all being subordi- 

 nate to the division which stands immediately 

 above them. Bach class is divided into orders, 

 each order into genera, each genus into species, 

 and each genus and species sometimes into 

 ra or subspecies. The term family is 

 sometimes used instead of genus, and objects 

 are often arranged in families, which again are 

 distinguished into varieties. 



CLAY. A well known constituent of soils 

 adding to them compactness and tenacity! 

 Under the head of Analysis, p. 91, is a table 

 showing a classification of soils, from which it 

 appears, that as a general rule, those exhibiting 

 the highest per-centage of clay, are esteemed 

 330 



CLIMATE. 



the most valuable. Although what is commonly 

 called clay, constitutes from 14 to 81 per cent, of 

 soils, its basis, alumina, or pure clay, exists only 

 in the proportion of from 72-100ths of 1 per 

 cent, in light sandy soils, to 5-25 per cent, in 

 heavier lands. Where it exists, as it often does 

 in sub-soils, in the proportion of 9 or 10 per 

 cent, good draining-tiles and building bricks may 

 be made of it. The clay from which the best 

 building bricks in Baltimore are made, contains 

 19| per cent, of alumina. (See BRICKS.) 



Clays have various colours, owinjr to admix- 

 ture with different substances. Yellow and red 

 clays are silicates of alumina with small propor- 

 tions of peroxide (or rust) of iron, united with 

 lime, magnesia, sometimes potash, and very 

 rarely soda. 



Strange to say in what are commonly called 

 on the Eastern shore of Maryland, and elsewhere 

 in the United States, "pipe clay or white oak 

 soils," very little pure clay exists, seldom over 

 3-75 per cent., in the upper stratum, and some- 

 times only about 1 per cent. According to Dr. 

 Higgins's analysis, 90 per cent, of this soil con- 

 sists of sand so fine as to lose its grittiness, whilst 

 the pure clay constitutes only about 2 or 2| per 

 cent. These white oak soils commonly rest on 

 a bed of white or mottled clay, which should 

 never be turned up in ploughing. They can ge- 

 nerally be rendered very productive by perfect 

 draining, with the addition of lime, ashes, or 

 guano. Such land is very unprofitable, unless 

 kept dry by numerous small ditches running into 

 a main ditch. See Ath"t, Mixture of Soils. For 

 the modes of burning clay in kilns, or dod-lurn- 

 ing, see Paring and Burning. 



CLICKLING. An unpleasant noise known 

 also by the term "overreach," which arises 

 from the toe of the hind foot of a horse knock- 

 ing against the shoe of the fore foot. If the 

 animal is young, the action of the horse may 

 be materially improved; otherwise nothing 

 can be done. 



CLIMATE OF THE UNITED STATES. 

 The temperature of the atmosphere constitutes 

 the principal element of climate. If the tem- 

 peratures of places depended solely upon the 

 position of the earth in relation to the sun, 

 then would every place receiving the rays at 

 a similar angle be similarly heated, and places 

 in the same latitude in every part of the globe 

 would have similar climates, so far as heat 

 was concerned. It would therefore be very 

 easy to classify climates according to relative 

 distances from the equator or proximity to the 

 poles. But observations made in different 

 parts of the world show that in similar latitudes 

 climates differ greatly, as is exemplified on the 

 two sides of the northern Atlantic, where the 

 mean temperatures of places on or near the 

 ocean are found to differ in some cases ten de- 

 grees of Fahrenheit, the climate of the European 

 coast being that much warmer, in its annual 

 mean temperature, than the American in the 

 same latitude. When, instead of mean tempe- 

 ratures, extremes of heat and cold are com- 

 pared, the difference is still more striking. 



Now, in explaining the rationale of this 



well known fact, we are compelled to refer to 



a grand natural phenomenon, which we shall 



designate the great atmospheric circulation. 



j This commences in the tropical region where 



