OF NATURAL HISTORY. 479 



port the torpidity of fwallows during the winter, likewife in- 

 forms us, that he himfelf met with them at fea, nine hun- 

 dred and twenty miles from any land*. 



Thefe, and fimilar facts, the Hon. Daines Barrington en- 

 deavours to explain, by fuppofing that birds difcovered in 

 fuch fituations, inftead of attempting to crofs large branches 

 of the ocean, have been forcibly driven from fome ccaft by 

 ftorms, and that they would naturally perch upon the firfb 

 vefTel which came within their view. 



In Britain, five fpecies of fwallows appear in the fummer 

 and difappear in the winter. 1. The houfe-fwallow makes 

 its appearance about twenty days earlier than the martin, or 

 any other of the fwallow tribe. They are often feen about 

 the 13th day of April. They difappear about the end of 

 September. A few days previous to their departure, they 

 aflemble in great flocks on the tops of houfes, churches, and 

 trees, from whence they are fuppofed to take their flight. 

 This unufual and temporary afibciation of numbers indicates 

 the impulfe of fome common inftinct by which each indivi- 

 dual is actuated. The houfe fwallow Is eafiiy dlftinguilhed 

 from the other fpecies by the fuperior forkinefs of its tail, 

 and by a red fpot on the forehead, and under the chin. 

 This fpecies build in chimneys, and make its neft of clay, 

 but leaves the top quite open. 2. The martin is inferior in 

 iize to the former, and its tail is much lefs forked. The 

 martins appear in Britain foon after the houfe-fwallow. 

 They build under the eaves of houfes : The neft is compof- 

 ed of the fame materials as thofe of the houfe-fwallow ; but 

 it is covered above, and a fmall hole only is left in the fide 

 for the ingrefs and egrefs of the birds. The martins totally 

 difappear about the beginning of October. 3. The f.^nd- 

 martin, or bank-martin, is by much the fmalleft of the fwal- 

 low-kind that vifit Britain. The fand-martins arrive very 

 * Voy, torn. I. page 24. 



