soMi: n:i<y /.o.vc i lii.nriioxr: cih\ ens 5(i7 



llu- liiu' at the time i>f tests ami llie a\era^;e total repealer aiiipiiti- 

 lalion from which can Ir- noted the amount of amplitiration recjiiired 

 to offset the \ariation in transmission e(|iii\ .ileni due to seasonal 

 lem|HTatiire changes. 



Conflusion — As mentioned earlier in this paper the data and results 

 given in the foregoing, although applying particularly to circuits 

 on the southern and central transcontinental routes, are also repre- 

 sentative of the conditions on other long circuits of the same type. 

 The establishment of these high (iiiality circuits, which are alsf) 

 available for the application of carrier systems and which in certain 

 cases have been so e(|uipped, constitutes another important step 

 in bringing together all sections of the country b\' telephone. 



