186 PETER COLLINSON [1751. 



represented upright : that yours should hang down, is very sin- 

 gular. 



All aquatic leaves have the property thou mentions, I presume, 

 from their downy surfaces, though not perceptible to our eyes with- 

 out a glass ; as all web-footed fowls shoot off the water from the 

 oily downiness that is on the surface. 



Thy expedition up the creek, shows with what energy thou pur- 

 sues nature. The hidden deeps cannot secure her treasure. She 

 rewards thy labours with her spoils. 



There is great reason to believe, from the beds of petrified shells 

 that are found all over the level country below the mountains, and 

 confined by the ocean, that its waves once washed the feet of those 

 hills, but, on some great revolution, retreated, and left those 

 memorials behind it. Indeed, we refer all such phenomena to the 

 effects of the Deluge; but it is believed, and also known, that there 

 have been great alterations on the face of nature, from earth- 

 quakes, &c. That Belemnites are found with sea-shells, I think is 

 a confirmation that they are marine productions ; which many 

 doubt, but think them stones, after their own kind, which, for 

 many reasons, I can by no means agree to. It may seem wonder- 

 ful to thee, that new shells are found, not known before : but who 

 can tell what lies concealed in the fathomless depths of the ocean ? 

 The Belemnites may lie concealed there ; their weight may prevent 

 their being washed on the shores. We have a cliff in England, 

 near Lymington, that abounds with such variety of shells. I have 

 at least twenty different species, large and small, all unknown on 

 our coasts, being from the East and West Indies. What a ren- 

 versement must this have been ! The productions of the South, 

 East, and West, thrown so far to the North ! 



I observe well, in thine of the 26th June, thy account of the 

 original building of the Swallows. I think it very feasible ; but 

 it is pretty singular none should continue their original institu- 

 tion. * * * * 



What thee calls Water Swallows, we call Sand Martins, from 

 their building in sandy precipices, near rivers, and in inland places 

 remote from them. They are, with us, of a different colour from 

 our chimney Martins or house Swallows. 



As to thy desire of an assistant, it would, to be sure, be of great 

 service, to relieve and assist thee ; but such as thou'd like is not 



