ELECTROMOTIVE FOUCES IN TUB VOLTAIC CELL. 



481 



air, it 



■0 that, 

 c" cx- 

 motiils 



I'Ues of 

 ,. Pov 

 i-c quite 



s views 

 so 'l)ase(l 

 clociActl. 

 M.V. «^f 



s shortly 

 diffrvcnl 



I observe, 

 of air ov 

 jfcnco of 

 Hit giisj^*^. 

 mdc witli 

 pcriinonts 

 perinicnts 



ng cxpcri- 



rrases. lie 



denser aro 

 ilm of tlio 

 erci-l witli 

 inonsation 



,.. But bo 

 [[ F. in the 

 mcr). He 

 d between 

 id it to the 

 ;e of lilnis 

 time for 

 ' the r^i^tes 

 it out and 

 late coated 

 tinuni, and 

 Hydrogen 

 , gold was 

 [e platinum 



Icompli^l'ed 

 \X chloride, 

 [o fact that 

 I\ t\ic phvtes 



von Mctalle" 



jrradually returned to nearly tlioir former state. ITo tried if bo could 

 iciiu'vc the gas film from one of the plates by exhaustit)n under an air- 

 pim.M, und the plate so treated exhibited a diHeronco wheu taken out and 

 (•omparn! \v;Ui an ordinary plate ; but ho was cautious enough to repeat 

 the experiment, leaving the plutc under the bell jar for the saTno time and 

 not exhanstiiig. Tho same dillcreneo appeared, so he attributes it to 

 possible grease. 



This is the rig.it sort of way to make experiments, and if everybody 

 experimented with proper care there would bo vastly fewer ])apers pub- 

 ILslied in Gernuiny, and science would progress on the whole faster. 



At present it feels to mo overkden vith u mass of publication, mostly 

 cC necessity by men of not absolutely the first order, much of it with no 

 Mirt of clearness or insight, bub rough, crude, and ill-digested. A man 

 1. lakes a number of experiments; he does not stop to critically examine 

 ••itid weigh them, and deduce from them their meaning, nor indeed does he 

 often take the trouble to examine whether any definite meaning can in 

 tlieir then shape be drawn from them ; bub he jnshes with them into 

 print, producing a memoir of wearisome length and sometimes extreme 

 illiterateiH'ss of style. 



Some one else then has the trouble of wading through the heap to see 

 wliothcr any fragments of value may perchance be imbedded in it, and 

 probably he is unable to como to much definite conclusion, because he 

 eannot be in .so good a jiosition fur criticism of the experiments as the 

 eriginal author was. He therefore writes a paper pointing out defects 

 mid errors in the communication. Others take up the same line, tho 

 "riginal man replies, and so there is a controversy, and nothing is really 

 settled at all. Finally, some one else independently goes over the whole 

 irrmind from some distinct point of view, makes a few well-planned, clear, 

 and decisive experiments, describes them in a compact and readable form, 

 and there results a definite gain to science. But how much better would 

 it have been if this last paper had been the only one published ! Unless a 

 man is an experimental genius of the highest order, it is necessary for him 

 to think for far more time than ho experiments, if he wishes to advance, 

 and not to lumber, his science. If it bo objected, as indeed it may with 

 great truth be, that one man's life and capacity are not sufficient for this 

 m the present state of knowledge, the objection constitutes a strong argu- 

 ment in favour of the proposition that the time has como for an organi- 

 but ion of science and a more definite division of labour. 



To return to tho experiments of Herr SchultzeBorge. One is not 

 nl)!c to say after all that they are very satisfactory, for the}- do not 

 distinctly settle any question. The general conclusion he draws from 

 them is the apparently safe one that the contact force between a metal 

 and a gas is not in general the same as between a metal and air. Even 

 this is not absolutely safe, however, because it might conceivably be that 

 an air /gas contact force caused all the diU'eronce. Granting that this is 

 unlikely, the experiments are in favour of a contact force between metals 

 and air or gas, but they do not establish the fact any more strongly 

 than, if so strongly as, Mr. Brown's experiments had already done: the 

 weak point in both is the possible corrosion of the plates and formation 

 of films of alloys or compounds, which may be the real source of the 

 okserved difference of potential. 



And against the existence of a contact force between metals and various 

 gases, the experiments of PcUatand others are to be remembered, which re- 



isn. ' ,1 



Ifl 



