19£l] Proceedings of Elisha Mitchell Scientific Society 3 



oped hydro-electric power in North Carolina. It is shown that there 

 is at present a total installed capacity of about 356,000 H. P. in plants 

 producing hydro-electric power. Of this, 80,000 H. P. or 22 per cent 

 is transmitted for use outside the state; 113,000 H. P. or 32 per cent 

 is used at Badin in the local reduction of aluminum; while only 164,- 

 000 H. P. or 46 per cent is available for general industrial and public 

 use. Of the latter 98,500 H. P. or 28 per cent of the total (60 per 

 cent of the 164,000 generally available) is developed by two large 

 public service corporations. 



The total output of electrical energy by public service plants has 

 increased 25 per cent from 1919 to 1920, and over 6000 per cent from 

 1907 to 1920. If the output increases at 12 per cent per year (one 

 half the present annual rate) there will be a demand in 1925 for 

 1,434,000 kw. hr. and in 1930 for 2,528,000 kw. hr. To meet this de- 

 mand, if the present proportion of output by water power is to be 

 maintained (85 per cent) there will be needed additional develop- 

 ment of 200,000 H. P. by water power in 1925 and of 624,000 H. P. 

 by 1930. To develop this amount of water power will mean many 

 new hydro-electric installations in the state, and the utilization of 

 most of the economically available water power sites. It is estimated 

 that about 1,500,000 H. P. is still undeveloped at sites in this state, 

 but only a portion of this amount can be economically developed 

 under present conditions. 



Fred F. Bahnson (Class of 1896), of Winston Salem, N. C.~The 

 Science of Humidification, with Demonstration of a New Humidifier. 

 Entirely too little attention has been paid to humidification in all 

 manufacturing processes except those where the advantages are very 

 plainly apparent, such as textiles. All materials of animal or vege- 

 table origin and a number of mineral origin are affected by the humid- 

 ity of the air in which they are stored or used, and this effect is pro- 

 portional to the relative humidity or percentage of saturation, rather 

 than the actual humidity or pounds of water per thousand cubic feet 

 of space. 



Since the weight of a. cubic foot of saturated aqueous vapor just 

 about doubles for each twenty degrees rise in temperature, it is ob- 

 vious that even if the out-door humidity is sufficiently high, the in- 

 door humidity will always be too low^ whenever artificial heat is used. 

 This simply means that artificial means of supplying moisture must 

 be used practically every day in the year, because even in summer 



