302 HISTORY OF BOTANY. 



are certain grasses which are called artificial, because they do 

 not spring up without cultivation ; of this kind is clover, a 

 leguminous plant, of the artificial class diadelphia ; Saintfoin 

 and Lucerne are of the same natural and artificial class. 

 Gramineous plants, although very important as furnishing 

 from their leaves food for cattle, are yet more especially use- 

 ful for their seeds which furnish food for man. 



Some plants furnish oils, which are of important uses in 

 various wavs. Of the fixed and volatile oils we have already 

 spoken. The fixed oils are extracted from plants called 

 oleaginous ; they may be considered under three heads, 1st, 

 olive oil produced from the olive in warm countries ; 2d, nut 

 oil of temperate climates, as obtained from walnuts, &c. ; 3d, 

 oil obtained from the seed of oleaginous or oily plants, as the 

 flax. 



Tuberous roots afford the turnip, potatoe, carrot, beet, pars- 

 nip, &c. which are all important articles of food. 



Asparagus when young is esteemed a luxury ; the rhubarb 

 plant is used in making pies ; celery, onions, and even garlic, 

 are esteemed valuable for food and seasoning. Many of the 

 labiate plants, as thyme, sage, &c. are used in cookery. The 

 Cruciform family presents us with the cabbage, cauliflower, 

 turnips, &c. The Leguminous family affords beans, peas, &c. 



The Cucurbitacece furnishes us with melons, squashes and 

 cucumbers. Umbelliferous plants present us with the aroma- 

 tics, caraway, coriander, &c. which are useful in medicine 

 and confectionary. 



LECTURE XLIII. 



History of Botany from the Creation of the World> to the Revival 

 of Letters in the reign of Charlemagne, A. D. 770. 



WE propose to give an account of the progress of botanical 

 knowledge ; and this being closely connected with other scien- 

 ces, you may consider it as a general view of the progress of 

 natural science. 



After becoming familiar with a science, the mind very natu- 

 rally seeks for information respecting its origin, and the pro- 

 gress by which it advanced from the first rude conceptions 

 which might have been formed, to its gradual developement 

 and comparative perfection. 



Oleaginous plants Tuberous roots Asparagus, &c. Cruciform, &c. 

 Melons Umbelliferous plants History of botanical science After becoming 

 familiar \vith a science we wish to know its history. 



