Mr. J. Aitken on Dew. 207 



each other. The aim and object of the greater part of the first 

 of these two papers appears to be to detract from the merit of 

 Dr. Wells's great work, bj endeavouring to show that almost 

 all the facts observed by him had been previously noted by 

 other investigators. As Mr. Tomlinson, however, just at 

 the end of his paper, reinstates Dr. Wells in the position he 

 previously occupied, perhaps nothing further need be said on 

 that part of the subject ; but as he has not been equally 

 generous to me, I must undertake the uncongenial task of 

 trying to put myself right with your readers. I will take Mr. 

 Tomlinson's remarks in the order of his paper, and as your 

 space is valuable, will make my reply as short as possible. 



At the very outset Mr. Tomlinson, by raising a false con- 

 tention, attempts to place me in opposition to recognized 

 authorities, by entitling his paper " Remarks on a new Theory 

 of Dew." The results of my investigation are in no sense 

 entitled to be called, and never have been called by me, a 

 " New Theory \ " nor w T as this so-called " new Theory of Dew" 

 " promulgated in opposition to that of Dr. Wells." My 

 work has not resulted in a new theory ; it is only an extension 

 of the work the foundations of which were laid by Dr. Wells. 

 The great fundamental principles established by that authority 

 are unaffected by anything contained in my paper. 



When Dr. Wells wrote his celebrated " Essay on Dew," he 

 must have been quite aware of the uncertainty as to the 

 source of the vapour. Although he appears to have thought 

 that but little of it could rise from the ground while dew was 

 forming, yet with admirable caution he adds, " He was not 

 acquainted with any means of determining the proportion of 

 this part to the whole," thus clearly recognizing the soil as a 

 possible source of the vapour. Wells's theory, however, has 

 principally to do with the condensation of the vapour after it 

 is in the air, and but little with its source. 



While quite agreeing with the author as to the difference 

 between " literary work " and "scientific work," and while 

 he in his comparison would extol the literary, I would rather 

 be inclined to consider the difference between literary and 

 scientific work to be so great that they cannot be compared. 

 Both are useful in their way. Mr. Tomlinson no doubt has 

 had sufficient experience as a thinker, a writer, and an in- 

 vestigator to have seen many a fair theory, apparently perfect 

 in all its parts, and consistently thinkable all through, vanish, 

 under the light of experimental test, like the baseless fabric 

 of a dream at the first touch of day. 



At pages 485-6 Mr. Tomlinson clearly states the chief 

 points, established by Dr. Wells, under six heads, and then 



