461 
in order to establish between this internal armature and a certain at- 
mospheric stratum an electrical equilibrium. On the other hand, a piece 
of tin foil rolled about the external tube in contact with the air com- 
municates with the soil. An interval of glass separates the tin foil and 
the platinum wire, and this interval is carefully coated with a triple 
layer of gum lae, in order to prevent any hygrometric loss and all com- 
munication between the two armatures. : 
In the annular space which separates the two tubes are placed strips of 
filter-paper, or two or three drops of a sirupy solution of dextrine, and 
pure nitrogen, or even ordinary air, subsequently introduced. The in- 
troduction of the gas and the different material is effected by means of 
a gas-tube soldered to the extremities of the apparatus, which are after- 
ward carefully closed with the lamp. This always precedes placing the 
armature of tin and the varnish of gum lac. 
Between the two armatures is established an electrical tension equal 
to that between the soil and a stratum of air two meters above it, the 
amount being deduced from the daily observations of atmospheric elec- 
tricity made with a Thompson-Branly electrometer at the meteorological 
station at Montsouris. With this electrical tension established, twelve 
tubes of fhe kind described containing respectively moist paper and 
moist dextrine, some of them being supplied with pure nitrogen, some 
of them with atmospheric air, all being hermetically sealed except two, 
which were so arranged that a current of air could pass through them 
and over their contents; all were ailowed to remain undisturbed for 
two months, and at the end of this time the material was found to have 
absorbed nitrogen, forming compounds which were decomposed by soda- 
lime at 300° to 400° C., with formation of ammonia. The amount of 
material employed in each of the tubes was less than one gram, while 
the amount of nitrogen taken up was valued at one or more milli- 
grams. It will thus appear that the quantity of nitrogen that may 
be fixed upon a surface covered with organic matter becomes consider- 
able from electrical intluences without taking into account other in- 
fluences so well known. 
In two of the tubes, Berthelot noticed the formation of green spots, 
due to microscopic alg, arising probably from germs introduced with 
the material. Im these tubes, more nitrogen was fixed than in any of ° 
the others. In one of the tubes supplied with pure nitrogen, the gas 
acquired a fetid odor. In the conclusion of his paper, Berthelot says: 
These experiments explain the influence of a natural cause upon vegetation, which 
has been quite considerable, but which has until now been almost unsuspected. 
Heretofore the study of atmospheric electricity in its relation to agriculture has 
been with reference to luminous and violent manifestations only, such as thunder and 
' lightning. In all hypotheses, only the formation of nitric and nitrous acids and nitrate 
of ammonia has been considered. Further than this, no doctrine relative to the 
influence of atmospheric electricity has yet been presented. Now, in my experi- 
ments, it has been a question of a totally new and absolutely unknown action, which 
takes place continually under a clear sky, determining a direct fixation of atmospheric 
nitrogeu within the proximate principles of vegetable tissues. In the study of the 
natural causes capable of affecting the fertility of soils, and of acting upon vegetation, 
causes which we endeavor to determine by meteorological observations, we should 
hereafter take into account not only differences in the action of light and heat, but 
_ also the electrical state of the atmosphere. 
NEW FEVER CURE—Croton adenaster.—In a late number of the “ El 
Oberrado Médicode Méjico? is descrived a plant of the family of Huphor- 
biacee, called picosa or euchiladera, (Croton adenaster,) which, on 
account of its febrifagic properties, has become a rival of the cin- 
chonas. According to the aualysis of Dr. L. M. Imenez, it contains an 
acid,a soft greenish resin having an acid reaction, a yellow olev-resinous 
