144  Prof.  W.  Weber  on  Electricity  in  relation  to 
the  increase  of  thermal  energy  found  by  observation,  it  would 
then  be  absolutely  necessary,  according  to  the  principle  of  the 
conservation  of  energy,  that  a  transference  should  take  place  of 
the  kinetic  energy  of  the  electrical  particles  in  the  Amperian 
currents  to  the  other  particles  whose  motion  constitutes  heat. 
And  indeed  it  would  be  needful  that  all  the  kinetic  energy  pro- 
duced by  the  current  in  the  electrical  particles  of  the  Amperian 
currents  should  be  completely  transferred  to  these  other  particles 
at  each  instant. 
But  apart  from  the  consideration  that  it  is  impossible  to  con- 
ceive how  such  a  complete  transference  could  take  place,  it 
is  self-evident  that  any  even  partial  transference  of  the  kinetic 
energy  of  Amperian  molecular  currents  to  other  particles  is  con- 
tradictory of  the  permanence  which  belongs  to  the  essential 
nature  of  Amperian  currents.  If  such  a  transference  of  kinetic 
energy  from  electrical  particles  in  molecular  currents  to  other 
particles  were  really  to  occur,  it  would  simply  prove  that  the 
molecular  currents  formed  by  these  particles  were  not  Amperian 
molecular  currents,  since  they  would  not  possess  the  permanence 
wherein  the  essence  of  Amperian  molecular  currents  consists. 
Hence  it  follows  as  a  consequence  that,  if  in  conductors  all  the 
electrical  particles  exist  in  the  state  of  aggregation  correspond- 
ing to  Amperian  molecular  currents,  the  observed  increase  in 
the  thermal  energy  of  a  conductor,  during  the  passage  of  a 
current  through  it,  must  result  immediately  from  the  increase  of 
the  kinetic  energy  of  the  electrical  particles  constituting  the 
Amperian  currents ;  that  is  to  say,  the  thermal  energy  imparted 
to  the  conductor  by  the  current  must  be  kinetic  energy  due  to 
motions  in  the  interior  of  the  conductor,  and  must  in  fact  consist 
in  an  increase  in  the  strength  of  the  Amperian  currents  formed  by 
the  electrical  particles  in  the  conductor. 
Reference  may  also  be  made,  in  connexion  with  the  identity  of 
thermal  energy  and  the  kinetic  energy  of  Amperian  molecular 
currents,  to  what  is  said  respecting  "  the  Transformation  of  the 
work  of  the  current  into  Heat,"  in  the  10th  volume  of  the 
Abhandlungen  der  K.  Ges.  d.  Wiss.  zu  Gottingen  (1862),  in  the 
33rd  section  of  the  memoir  entitled  "  Zur  Galvanometrie." 
20.   On  Thermomagnetism. 
The  following  remark  readily  connects  itself  with  the  hypothe- 
sis of  the  previous  section,  that  the  electricity  in  conductors 
exists  in  the  state  of  aggregation  corresponding  to  Amperian 
molecular  currents — and  with  the  consequent  identity  of  the 
thermal  energy  of  the  conductor  and  the  kinetic  energy  of  the 
Amperian  currents  in  the  conductor — namely,  that  equality  of 
temperature  in  two  conductors  must  depend  upon  certain  rela- 
