164 GILBERT WHITE OF SELBOR]SrE 



1768 



that tho' the swift is at its arrival of a dark sooty colour; 

 yet by being for 16 hours together almost constantly in the 

 sun and air, it becomes before its departure much bleached, 

 and as it were what the country people call piss-burnt, like 

 an old weather-beaten brown wig : and yet it returns sooty 

 again in the Spring. N'ow if they go into warm regions 

 during our winter, why do they not return sun-burnt, as 

 they went off ? It is a matter of curious enquiry to consider 

 when swifts moult. Change their feathers here they 

 certainly do not: and if they have as much occasion for 

 their wings while absent, as while here, they would find no 

 opportunity to spare several feathers at a time. I would 

 not pretend to lay too much stress on these reflections, but 

 certainly can't refrain from observing that they tend rather 

 to make one suspect that they hide, rather than migrate — 

 at least for part of the long time they are absent from us ; 

 and perhaps at that juncture they moult." 



Letter XX. to Pennant, dated October 8th, 1768, 

 began — 



"Your letter of September 6th gave me a great deal of 

 entertainment and satisfaction ; and the more satisfaction 

 because I really began to fear from your long and unusual 

 silence that you might be prevented from writing by sickness 

 or some accident that might have befallen you in your 

 Caernarvon tour. But as I much esteem your friendly cor- 

 respondence already, I desire you will not make use of any 

 such methods of enhancing the value of it for the future. 



" I receive your kind invitation into Flintshire as a fresh 

 instance of your friendly disposition towards me; but whether 

 my health, or the want of command of my time will ever 

 permit me to gratify myself with so pleasing a tour and 

 visit, I cannot pretend to say ; however I depend much on 

 having it in my power to give you a meeting in town next 

 spring : and it would be a matter of high entertainment and 



