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THE NATIONAL GEOGRAPHIC MAGAZINE 



the neck of the bottle resting on the edge 

 of the bucket. Then I took a long glass 

 tube, over a meter in length, and put one 

 end into the bottle and the other end in 

 my mouth. I sat back comfortably in a 

 chair with the tube between my lips and 

 inhaled through the nostrils and blew 

 down through the tube. This process 

 was so easily performed that I found I 

 could read a book while it was going on. 



I therefore continued the experiment 

 for over two hours, and then I found a 

 considerable amount of water in the bot- 

 tle, quite enough for a moderate drink. It 

 might not be very much for us, but if 

 you were dying of thirst on the open sea 

 you would be glad enough to get what 

 was there. I tasted the water and found 

 it quite fresh, although I must confess it 

 did not have a very palatable taste ; in 

 fact, the water condensed from my breath 

 had a taste of — of tobacco ! But I don't 

 suppose that would have mattered much 

 to a man who was dying of thirst. 



I have also made experiments to con- 

 dense drinking water from fog. A large 

 pickle jar was provided and two long 

 glass tubes were let down through the 

 cork. The jar was then submerged at 

 the wharf, with the two pipes sticking up 

 above the surface. The experiment was 

 then made to pump fog down through 

 one of the pipes, the other serving as a 

 vent. This was accomplished by means 

 of a pair of bellows provided with a 

 spiral spring between the handles to keep 

 them apart. This apparatus was fastened 

 on top of the wharf. A heavy log of 

 wood was floated upon the water below, 

 connected by means of a string with the 

 upper handle of the bellows. 



THE CORK THAT FAILED 



The waves moved this log up and down 

 and worked the bellows. The nozzle was 

 connected to one of the pipes leading to 

 the submerged empty jar and at once the 

 bellows began to pump the fog into the 

 jar. It continued pumping all night, and 

 I let it go on pumping all of the next day. 

 because there was to be a meeting of men 

 on my place the next evening, and I 

 thought it would be interesting to open 

 the jar at the men's meeting. With great 

 ceremony the iar was removed to the 



warehouse and was found to be nearly 

 full of beautiful clear water. A British 

 naval officer was present and offered to 

 be the first to taste the water condensed 

 from fog. He took a good mouthful of 

 it, while the men gathered around in great 

 excitement and shouted, "Fresh or salt?" 



He did not reply, but made a face. He 

 then rushed for the window, spat the 

 water out, and exclaimed, "Salt!" Now, 

 this failure did not by any means prove 

 that the process was wrong, but simply 

 showed that it might be advisable in the 

 future, if you use a cork, to employ one 

 that fits tightly and does not leak. The 

 one I used had a hole in it, I found out 

 afterward. 



An involuntary experiment relating to 

 the condensation of fresh water from the 

 sea was made in Cape Breton. A man 

 fell overboard and was rescued, with his 

 clothes wringing wet with sea-water. 

 There was a cold wind blowing and he 

 took refuge in a little cabin on the boat 

 covered with a tarpaulin awning. In a 

 little time he began to steam. The heat 

 of his body warmed the sea- water in his 

 clothes, and there actually arose a cloud 

 of steam which condensed on the cold 

 tarpaulin and ran down the sides. It was 

 fresh water, and if it had been collected 

 in a jar there would have been quite 

 enough for a drink. 



"we do xot boil the sea" 



On large ocean steamers all the drink- 

 ing water used is condensed from the 

 sea ; and we somehow or other have the 

 idea that it is necessary to boil the sea- 

 water, or at least have it very hot, and 

 then condense it by means of ice or some- 

 thing very cold. Now, that is not neces- 

 sary at all. Just think of this : All the 

 fresh water upon the globe comes from 

 the sea, and we do not boil the sea. Water 

 vapor is. given off by the sea everywhere 

 and at all temperatures ; it is even evap- 

 orated from ice and snow. Of course, 

 the warmer the sea-water is, the greater 

 is the amount of water vapor thrown 

 out : but water vapor is everywhere pres- 

 ent, and the main point in condensation 

 is that it is removed from the surface by 

 the action of the wind and carried to 

 cooler places, where condensation occurs 



