146 NATURAL SCIENCE. March, 



But in a directer fashion Argon seems to offer promise to biology. 

 It is a constituent of the atmosphere, and enters the lungs and the 

 air-chambers of animals and the tissues of plants. It is twice as 

 soluble as nitrogen, and, no doubt, actually enters that flux of 

 substances we call the living substance. Does it leave it unchanged ? 

 Is it a casual visitor, as impertinent to the stream of life as are 

 straws to the current of a river ? Here, as soon as a convenient 

 method of preparing Argon be found, is a field that must be explored 

 by the physiologist. It is certain enough that the most common 

 events of protoplasmic respiration are not known in detail so minute 

 as to exclude the operation of unknown factors. The exact influence 

 of Argon upon vital phenomena must be determined as soon as 

 possible. More than this, its relation to proteids must be inves- 

 tigated. That is an obvious piece of work that already may be in the 

 doing. It is true Professor Ramsay found no Argon in the nitrogen 

 prepared from urea. But as Argon will not combine with oxygen, its 

 absence in urea by no means excludes the possibility of its presence 

 in proteids. 



Sir Robert Ball and the Cause of an Ice Age. 



The Geological Magazine has begun under its new publishers 

 Dulau & Co.) with two very interesting numbers. The most remark- 

 able paper is a criticism on the astronomical theory of the Ice Age, by 

 Mr. E. P. Culverwell, the second part of which appeared in the 

 February number. Mr. Culverwell's criticism of Croll's theory 

 simply confirms the view of its absolutely untrustworthy nature, 

 which has long been held by geologists. The most startling 

 part of the paper is, however, his attack upon Sir Robert Ball's pre- 

 tensions to have corrected and improved Croll's statement of the case. 

 Culverwell argues that the Cambridge Professor has done nothing for 

 the astronomical theory except misunderstand and misrepresent it. 

 He proves that the supposed fundamental error in Croll's argument, 

 which Sir Robert claims to have discovered " and which it is the chief 

 object of [his] book to expose" is a mere mare's nest. Sir Robert repre- 

 sents Croll as saying that the heat received in summer is equal to that 

 received in winter. This, of course, is not the case, and Culverwell 

 quotes several passages from Croll which show that he said nothing so 

 erroneous. In fact, in the main difference between Croll and Sir Robert, 

 all the advantages are with the former ; his statement is more correct 

 and would account for a greater difference in climate than the theory 

 as modified by Sir Robert. All readers of the latter's little book will 

 remember the wearisome reiteration with which the numbers 63 and 

 37 are used. They are conjured with all through the book. The author 

 gives no justification for their adoption, but declares that it is im- 

 possible to discuss any astronomical theory of the Ice Age in which 

 these magic numbers do not form the refrain of every argument. But 



