236 



KNOWLEDGE 



[OCTOBEB 1, 1898. 



species are characterised by the presence of resin, and the 

 woody species by their extreme hardness. The most im- 

 portant economic species of the order are Guaiacum 

 oj/iciiutir and ti. sancluiii, both of which furnish the well- 

 known hard wood, Lignum vit;e, of commerce. The first 

 is a tree of twenty or thirty feet high, crowded with 

 numerous, spreading, jointed branches, covered with long 

 green leaves and numerous bright pale blue flowers, 

 which give the tree a very handsome appearance. It grows 

 in most of the West Indian Islands, more particularly in 

 Hayti, .Jamaica, and Cuba, and is found also in Columbia 

 and Venezuela. The second species, a . sunvtuin, grows in 

 Cuba and the Bahamas, but is not found in South America, 

 though it occurs at Key West, in Florida. Guaiacum wood 

 or Lignum vitse is imported in large logs or billets, 

 weighing sometimes as much as a hundredweight. The 

 bark is removed before exportation. The wood is often 

 as much as a foot in diameter, and shows on a cross 

 section a marked distinction between heartwood and 

 sapwood, the former being of a dark greenish colour, 

 owing to the presence of resin, which is known commer- 

 cially as gum guaiacum, and the sapwood being of a light 

 yellow, containing no resin. The heartwood is one of 

 the darkest and hardest woods known, and is valued for 

 these qualities as well as for its great durability, for which 

 reason it is used largely for making ships' blocks, pulleys, 

 skittle balls and bowling balls, rules, pestles, etc., and 

 medicinally as a stimulant, diaphoretic, and alterative. 

 It was formerly much used in syphilitic and cutaneous 

 affections, chronic rheumatism, gout, scrofula, and similar 

 diseases. For these purposes it was seen in chemists' 

 shops in the forms of chips, shavings or coarse powder. 

 It is, however, seldom used medicinally at the present 

 time. The best kind of Lignum vitie comes from San 

 Domingo ; other qualities are imported from Hayti, Baha- 

 mas, and Jamaica. 



Guaiacum resin occurs either in lumps or small round 

 pieces known as tears. Externally it is of a brownish- 

 green colour, breaking with a clean, glassy green fracture. 

 It has no smell, except when warmed or rubbed, when it 

 emits an aromatic odour. It possesses the same pro- 

 perties as the wood, and is used in medicine for similar 

 purposes. 



A curious plant belonging to this order is that known as 

 the creosote plant {Lama mexicana), a shrubby plant of 

 North America. A resinous substance or lac covers the 

 twigs, which is scraped off' by the Indians and melted into 

 balls. It is considered by them as efficacious in the case 

 of rheumatism. 



Geraniace.e. — A group of herbs or shrubs distributed 

 over the globe, the Pelargoniums being found abundantly 

 at the Cape of Good Hope. The characteristic properties 

 of the plants are astringent, aromatic and fragrant. They 

 are, however, more valued, horticulturally, for the beauty 

 of their flowers than for their economic properties. From 

 this point of view the most important is, perhaps, the 

 rose leaf geranium [PAunjoniuw rajiitntia/i), which is 

 largely cultivated in the South of France, Turkey, Algeria, 

 and Spain, for the fragrant oil which is distilled from its 

 leaves, and is used as a perfume, both by itself and for 

 adulterating attar of rose. Sanacaulon lleriticri, a fleshy 

 plant of the Cape, is peculiar in having a cylindrical stem 

 which, in its older stages of growth, becomes so highly 

 charged with a hard wax that all traces of vegetable tissue 

 are lost, and the stem breaks with a short brittle fracture. 

 It burns freely, and is sometimes used as a torch or 

 candle. 



The acid character of the plants of this order is well 

 developed in the Blimbing of India {Averrhoa UUimbij, 



belonging to the tribe Oxalideae. It is a small tree, much 

 cultivated in India for the sake of the fruit, which is 

 cylindrical in shape, about three inches long and one inch 

 in diameter, somewhat resembling a gherkin. It is 

 extremely acid in its fresh state, but is often preserved in 

 syrup, or candied, or used as a pickle. The carambola is 

 a closely allied fruit, native also of the East ; it differs, 

 however, in shape from the Blimbing as it is distinctly 

 marked with prominent ribs or wings running parallel 

 down the sides of the fruit. It is the produce of Aierrlwa 

 Caramhohi. From the wood sorrel (< ixalis acetosella) oxalic 

 acid is prepared, while the tubers of several other species 

 of Oj-alia are edible ; such, for instance, as O. crenaUi, a 

 native of Peru, but much cultivated about Lima. The 

 tubers are about the size and shape of large walnuts, but 

 are not unlike small potatoes in general appearance. Their 

 naturally acid flavour is dissipated by cooking when they 

 are eaten by the people, and are occasionally seen in the 

 markets of this country. At the time of the early potato 

 murrains it was thou;,'ht that the tubers of ttiis oxalis 

 might under cultivation become a regular substitute for 

 the better known tuber, but this has never been reaUzed. 

 Other species, the tubers of which are eaten in Bolivia 

 and Mexico, are ". ttderosa and O. Depjiei respectively, 

 both of which were recommended for cultivation with us 

 along with ". crenata. 



KuTACE.Ti. — This large and very important order consists 

 chiefly of trees and shrubs, widely scattered over the 

 warmer temperate regions of the globe, being especially 

 numerous in Australia, South Africa, and tropical America. 

 The order is characterized by the presence of bitter, 

 aromatic, or fragrant oils, found abundantly in glands 

 covering the leaves or fruits, as in the rue and the orange 

 tribe, and in wart-like protuberances in the species of 

 Zanthojiiluin. The order is of much value from an 

 economic point of view in consequence of its including the 

 several species of ' itrus, furnishing the oranges, lemons, 

 and citrons of commerce. These fruits are far and away 

 the most important products of the order, notwithstanding 

 there are many others of very varied interest and value. 



The sweet orange, which is also known as the Chinese 

 or Portugal orange, is the fruit of Citrus Auruntiuin, a 

 small, much branched tree of about twenty feet in height, 

 which is scarcely known at the present time in a wild 

 state, but which seems to have been originally a native 

 of Northern India or Southern China, and not intro- 

 duced into Europe till the middle of the fifteenth century. 

 At the present time the sweet orange is cultivated very 

 extensively in many parts of the Mediterranean district, 

 as well as in Spain, Portugal, Madeira, the Azores, and 

 many other countries possessing a suitable climate. In 

 the South of Europe the trees tiower in April and May, 

 and the fruits ripen about a year after. A very large 

 number of varieties of the orange have been described, 

 the most important being those affecting the size, form or 

 quality of the fruit. The more important varieties are 

 those known as the China orange, the St. Michaels, the 

 Blood or Malta, in which the pulp and juice are of a blood- 

 red colour, the Mandarin and Tangerine. Orange trees 

 are remarkably prolific fruitbearers.andit has been stated on 

 good authority that one tree has been known to yield twenty 

 thousand fruits fit for exportation. Enormous quantities 

 of fruits, which are ever increasing in bulk, find their way 

 into the English market, and when it is borne in mind 

 that each fruit has to be gathered separately, wrapped in 

 paper and packed, together with the cost of the boxes, 

 freight and labour throughout, and after all this the fruits 

 can often be sold in the retail market at twenty for a 

 shilhng, it seems very remarkable that the crops are made 



