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interest than the paper which has just been read by Mr. Frank 

 Shuman. It almost seems presumptuous to think that we can 

 make a servant of the sun, but Mr. Shuman has described so 

 clearly the way in which he proposes to take such a liberty with 

 the sun and, in fact, has already done so -that one is certainly 

 inclined to think that even if he has not already solved the 

 problem he is, at all events, on the verge of an immense 

 discovery with unlimited power for good. The possibility of 

 using the sun as a producer of heat and energy on this earth 

 opens up a vast vista of possibilities, and the clear way in which 

 the lecturer has described his process must have made most of 

 us think we were- hearing of something almost too good and 

 too simple to be true, and we wondered perhaps why it had 

 not been done before. But we know that the most simple 

 things are often thought of last. You have all listened to Mr. 

 Shuman's exposition with close attention, and I am sure his 

 kind consent to answer questions will be taken advantage of 

 by many present. 



Mr. E. E. GREEN : May I ask what the cost would be for 

 one of the smallest installations ? 



Mr. SHUMAN : Well, roughly speaking, it would be about 

 31 per horse power. You could practically build installations 

 down to 5 horse power, but of course it would be better to 

 have one central plant of more convenient size, and then 

 transmit electric power to the small places round. 



Sir J. WILSON: I know parts of India where we sometimes 

 want irrigation considerably more in the cold weather than in 

 the hot. In the places I have in mind the sun is not nearly so 

 powerful as we are accustomed to think of it in connection 

 with India; in fact, it is only a little hotter than it is in England 

 in the summer. Would this method be able to develop any 

 useful power in such a case as that? 



Mr. SHUMAN: That is a very interesting question. As I 

 point out in my paper, the sun does not throw heat rays on 

 the earth ; it simply throws light rays, and unless these light 

 rays are absorbed no heat is produced. It is not a question of 

 atmospheric temperature so much. If a sun-power plant were 

 put up in a place where the temperature is below zero, of 

 course there would be a little more loss by conduction into the 

 surrounding atmosphere. In London here, on some of your 

 bright sunshiny days, you could run a plant just as effectively 

 as in the tropics. The only reason why a sun-power plant 

 would not be effective all over the world is that in most parts 

 of the temperate zone there are not sufficient hours of sunlight 

 during the year. In America our very best tests were made 

 when there was snow on the ground, and the temperature was 

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