Review?. — Lindle\fs Theory of HorlicuUure. 31 



merit. Concerning these interesting subjects, much may be 

 gathered in Chapters XV^II. and X\'1II. 



Every propitious experiment or result in horticulture, has 

 been based on certain natural phenomena, peculiar to whatever 

 plant they are made in reference to. The forcing of the 

 grape at unusual seasons, though the result of experiment, yet 

 is founded on the great law of rest, and a season for receiving 

 a new supply of excitability. Patience and perseverance 

 might bring about similar results in many of our finest flowers. 

 Undue excitability at one time must be balanced by an undue 

 season of rest at another. Our long, cold winters, seem to 

 us to be the cause of our primal sterility; whereas they are 

 only the accompaniments. The vivid and gorgeous flora of 

 the tropics is only periodical, and after a few weeks of ver- 

 dure and splendor, the season of rest is a season of sterile 

 aridity. 



At the Cape of Good Hope there are districts in which the period 

 of wet is long and very severe; and many of the favorite flowers of 

 our gardens are produced by those di?;tricts. The Karroos are 

 plains of great extent, destitute of running water, with a soil of clay 

 and sand, colored like yellow ochre by the presence of iron, and 

 lying on the solid rock. During the dry season the rays of the sun 

 reduce the soil nearly to the hardness of brick: Fig Marigolds, Sta- 

 pelias, and other fleshy plants, alone remain green; nevertheless, 

 the bulbs and tribes of Iridaceous and other plants are able to sur- 

 vive beneath the sun-scorched crust, which appears indeed to he 

 necessary to their nature. But in the wet season these bulbs are 

 gradually reached by the rain; they swell lieneath the earth; and at 

 last develop themselves so simultaneously that the arid plains be- 

 come at once the seat of a charming verdure. Presently af^terwards, 

 myriads of the gay flowers of the Iridaceaj and Mesembryanthemutns 

 display their brilliant colors; but in a few weeks the verdure fades, 

 the flowers disappear, hard dry stalks alone remain; the hot sun of 

 August, when in those latitudes the days begin to lengthen, com- 

 pletes the destruction of the few stragglers that are left, the Karroo 

 ajrain sinks into aridity and desolation, and the desert reappears. 

 What succulents survive ai'e covered with a grey crust, and derive 

 their nourishment only from the air. In other parts of the Cape of 

 Good Hope the mean range of the thermometer in winter is 48° to 

 93^, with cold rain, while that of the sunnner is from 55^ to 96°, with 

 dry days and damp nights. 



The concluding Chapter treats of "soil and manure," in a 

 brief and succinct manner. Of these indeed little can be said 

 without tedious detail, after the foregoing principles and ap- 

 plication to horticultural science. The importance of attend- 

 ing to the difference of soils in which species of the same ge- 



