146 Ci-ystallisation of Gold, 



former, in proportion to the size of the foot, this supposition is 

 not without foundation. 



Professor Buckland has given the credit of the foot-marks 

 to an animal of the genus Testudo. A comparison has been 

 ingeniously instituted by that gentleman between the foot- 

 steps in the stone and those made by recent tortoises. For 

 this purpose he has caused live animals of that genus to walk 

 over soft clay or dough, and the result tends decidedly to con- 

 firm his opinion ; and here it may not be out of place to notice 

 some observations made by a writer in a late number of the 

 London Magazine* upon this subject. It is there remarked, 

 '' They (the Geological Society) had much better have re- 

 frained ; for when the tortoise was at length prevailed on to 

 walk, he insisted on walking as straight as an arrow ; whereas 

 the antediluvian tortoise's march was as crooked as a ram's 

 horn." Now, it happens unfortunately for this statement, that 

 the marks in the sandstone rock run in a direct line. It is 

 true, the tortoise showed at first some unwillingness to stir, 

 but, when he did move, he proceeded forward in quite as 

 straight a course as his " antediluvian" progenitor. 



No remains of the tortoise have hitherto been found in strata 

 older than the lias ; but we must not, on that account, refuse 

 to believe that they existed at a still earlier period. The dis- 

 <;overies that are made every day in geology, though they tend 

 to confirm and establish that science, should yet teach us how 

 much remains to be learned respecting it. 



K.N. 



Art. X. On the Crystallisation of Gold, By the Rev. John 

 Stevens Henslow, Professor of Botany in the University of 

 Cambridge. 



Dear Sir, 

 The crystallisation of gold from a state of fusion is on 

 record; but I am not aware that any one has observed a 

 similar effect to have resulted from its solution in acid. Per- 

 haps, therefore, you may consider the following notice worth 

 Inserting in the Naturalist's Magazine. 



Yours, &c. 

 Cambridge, March, 1828. J. S. Henslow. 



A small glass-stoppered vial, containing a solution of gold 

 in a mixture of nitric and muriatic acids, had stood neglected 



* London Magazine for March, 1828, p. 356. 



