Page:The Scientific Monthly vol. 3.djvu/182

 176 THE SCIENTIFIC MONTHLY

a form of radiant energy. While developed in a number of liri mala — including the typical glowworms in which the phenomeo first investigated by Faraday — ^the living condition is not essenti because the phosphorescence continues after death and may be pi in animals by non-living material. Many organisms show phoa; cence at comparatively low temperatures^ yet the presence of free appears to be necessary.

Finally, we observe that ionization is connected with the radi elements, of which thus far only radium has been detected organic compounds although the others may be present.

The ionizing electric properties of the life elements are a ma first importance. We observe at once in the table below that i great structural elements which make up the bulk of plant and [ tissues are of the non-metallic group with negative ions, with the exception of hydrogen which has positive ions. All these elemei of low atomic weight and several of them develop a great amo heat in combustion, hydrogen and carbon leading in this function

TABLE n

The Lipe Elements, showing their Principal Properties and Functi

Plants and Animals

��Mainly or WboUy with or In Necatlve lou'* Mainly or WboUy with or In Podtivi

��Non-metallle Metallic

��n Carbon (0. (7..^ carbonates) Silicon

^* Oxygen (e. 9./* sulphates) Iodine

^ '4 Nitrogen (e. g.,''* nitrates) Bromine

n Phosphorus (e. 0.,^* phosphates) Fluorine n Sulphur (e. a**'* sulphates ) Boron

Chlorine ^* Arsenic

��"" Hydrogen

�••Iron

�lit]

�Potassium

�Copper

�Hi<

�Sodium

�Aluminum

�Ra(

�Calcium

�Barium

�Str

�Magnesium

�Cobalt

�Zin

�Manganese

�Lead

� ��Ionization Elements thus far Discovered in Living Organ

72 An ion is an atom or group of atoms carrying an electric charge, positive ions (cations) of the metallic elements move toward the cathod* negative ions (anions) given off by the non-metallic elements move towa anode.

78 Together with hydrogen conspicuous in living colloids and non-electi • — ^very little in the indicated ionized forms.

74 Occurs also, as NH4, in positive ions. Here the hydrogen overbalanc nitrogen.

7B Substances occurring in living matter.

79 Arsenic itself is a metal, but in living compounds it is an analogue of phorus and occurs in negative ions when ionized.

77 Pictet has obtained results indicating that liquid and solid hydroge metallic. Hydrogen is metallic in behavior, though non-metallic in appea\

78 Iron in living compounds is chiefly non-ionized, colloidal. Apparentl; is also true of copper, aluminum, barium, cobalt, lead, nickel, strontium and As to radium, however, there is no information on this point.

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