Dr. W. H, Eccles on Coherers. 877 



Discussion of Results. 



The most striking outcome of the measurements is embodied 



in fig. 3. The curve connecting the power delivered to a 



coherer as electrical oscillations and the power passed by the 



Fig. 3. 



4-0 



2-0 



10- 9 Watt 













... *f + 



s X 



10' 8 Watt 



w 



Iron-Mercury Detector. 



"W = power supplied as oscillations. Resistance about 1000 ohms. 

 Oscillation amplitude at coherer=442x VW volt. 



coherer to the telephone turns out to be a straight line passing 

 nearly through the origin. The line is different for different 

 values of the steady electromotive force applied to the 

 detector. The upper curve of fig. 3 was obtained from a 

 rather insensitive coherer, which happened to have a resist- 

 ance of about 1000 ohms at its most sensitive voltage, the 

 iron being positive. The lower curve is one selected under 

 similar considerations with the iron negative. The approxi- 

 mate equation of the former is 



of the latter is 



w; = 0-024(W-0-DxlO- s ), 

 w = 0'019(W-2-2xlO- 8 ), 



the unit being a watt. All the other curves that have been 

 obtained with coherers of various construction, resistance, 

 applied E.M.F., are very like these. The more sensitive the 

 coherer the steeper the line, is the only rule that has yet come 

 to light (and in some iron-mercury coherers the gradient of 

 the line is 0'06) ; there is no rule yet proved for the constant 



