173 CUBBENT ELECTBICITY CHAP. XII. §. II. 



water was still positive. According as the surface of 

 the root in the water was greater, so was the effect 

 upon the needle increased. The sap from the roots 

 reddened litmus paper. 



Hyacinth and narcissus bulbs were made to vege- 

 tate in the usual glass vessels. The electrode in 

 contact with the water and at the extremities of the 

 roots was positive to the other when inserted into the 

 stem or bulb. The bulb was raised so as to leave 

 the fibrillae alone in the water ; the effect was much 

 diminished, and almost nuU. The water was rendered 

 slightly alkaline by means of potash; the effects were 

 still the same. 



The sap in the fibrillaB and bulb reddened litmus 

 paper. 



The same experiments were made as with the 

 leaves, namely, coating the electrodes with acid or 

 alkaline solutions. Whichever electrode was coated 

 with the acid, was always positive to the other. 



Becqueeel 1 has made the following remark : 

 " On obtient peu ou point d'effet, lorsque I'une des 

 aiguilles est dans le ligneux, pres de la moelle, et 

 I'autre dans la terre.'' 



According to Lindlet', Brugmans has ascertained 

 that some plants exude an acid fluid from their 

 spongioles. 



Some experiments are also related by Becqueeel', 



1 In his first Memoir. 



■■ Introduction to Botany, p. 229. 



• Traits de I'Electricit^, tome iv. p. J 85. 



