i6o NATURAL HISTORY 
before the reft. Thefe approaching the eaves of buildings, and play- 
ing about before them, make people think that feveral old onea 
attend one neft. They are often capricious in fixing on a nefting- 
place, beginning many edifices, and leaving them unnnilhed ; but 
when once a neft is completed in a Iheltered place, it ferves for 
feveral feafons. Thofe which breed in a ready finifhed houfe get the 
ftart in hatching of thofe that build new by ten days or a fortnight. 
Thefe induftrious artificers are at their labours in the long days be- 
fore four in the morning : when they fix their materials they plafter 
them on with their chins, m.oving their heads with a quick vibratory 
motion. They dip and wafh as they fly fometimes in very hot 
weather, but not fo frequently as fwallows. It has been obferved 
that martins ufually build to a north-eaft or north-weft afped, that 
the heat of the fun may not crack and deftroy their nefts : but in- 
ftances are alfo remembered where they bred for many years in vaft 
abundance in an hot ftifled inn-yard, againft a wall facing to the 
fouth. 
Birds in general are wife in their choice of fituation : but in this 
neighbourhood every fummer is feen a ftrong proof to the contrary 
at an houfe without eaves in an expofed diftridl, where fome mar- 
tins build year by year in the corners of the windows. But, as the 
corners of thefe windows (which face to the fouth-eaft and fouth- 
weft) are too fliallow, the nefts are wafhed down every hard rain ; 
and yet thefe birds drudge on to no purpofe from fummer to 
fummer, without changing their afpedt or houfe. It is a piteous 
fight to fee them labouring when half their neft is wafhed away and 
bringing dirt " generis lapji farcire ruinas". Thus is inftind a 
moft wonderful unequal faculty; in fome inftances fo much above 
reafon, in other refpeds fo far below it ! Martins love to frequent 
towns, efpecially if there are great lakes and rivers at hand ; nay 
they 
