Agriculture. 381 



The influence of Light on j^rowing vegetables 

 has also been investigated with great success by- 

 many modern philosophers. Among these Hales, 

 Priestley, Abbe Tessier, Ingenhouz, and Sen- 

 NEBiER are entitled to particular distinction. From 

 the experiments of these philosophers, it appears 

 that this subtle fluid has a powerful eflect on the 

 colour of vegetables-; that when exposed to its in- 

 fluence, it enables them to yield pure air; and that 

 it converts many substances, w4iich w^ould other- 

 wise become putrid and ofl^ensive, into whole- 

 some food of plants. 



The eflicacy of Electricity in forwarding tlie ger- 

 mination and growth of plants, was discovered 

 and satisfactorily established by the philosophers 

 of the eighteenth century. It was before re- 

 marked that Mr. Maimbray, of Edinburgh, was 

 the first who applied electricity to this object. 

 He was followed by theiVbbe Nollet, Mr. Jal- 

 LABERT, M. BozE, and several others, who all 

 formed the same conclusions. Still more recently 

 the w^ell devised and indubitable experiments, of 

 Messrs. D'Ormoy, Rozier, Carmoy, and Bar- 

 tholon, all of France, have thrown additional 

 light on the subject, and substantially confirmed 

 the results of preceding experiments. 



The influence of various Factitious Airs in has- 

 tening and retarding the progress of vegetation, is 

 a branch of agricultural inquiry peculiar to the 

 eighteenth century. On this subject the successive 

 experiments of Dr. Hales, Dr. Priestley, Lord 

 DcjNDONALD, Sir Francis Ford, and Dr. Dar- 

 win, of Great-Britain; of Hassenfratz, and 

 several other French Chemists; and of Jacquin, 

 Von Uslar, and Von Humboldt, of Germany, 

 have furnished very interesting and important in- 

 formation. 



Besides the new substances employed for pro- 



