On the Swallow. 279 
rations the grand master builder, who is sometimes relieved by 
turns, shows his skill and experience in the art of building, by 
proportioning the radius of the nest, the acuteness or obliquity of 
the angles, in strict proportion to the distance and bearing of the 
abutments, and thickens the wall proportionately to the te- 
nacity of the materials, every morsel of which he carefully exa- 
mines before it is laid on, and if satisfactory, a pleasing chit-chat 
passes between the parties. But if insufficient, in any respect, 
the tone of the grand master is soon changed, and a violent 
altercation takes place. I have seen the imperfect materials 
rejected and thrown down with great apparent wrath and in- 
dignation, and the carrier dispatched with a scold for a fresh 
load. It was during my attention to these little operations that 
I first conceived them possessed of the gift of speech. Would 
any one, who may have time and opportunity, with an ear capa- 
ble of distinguishing the minute variations of sound, attentively 
listen to the different conversations that pass on these occasions ; 
the orders given, and communications received ; the varied ca- 
dence of the articulated notes ; the pleasing mildness with which 
this is conducted in good humour; the fierce volubility and fu- 
rious manner in cases of reproof or scolding; I am satisfied an 
impartial auditor would mark these wonderful migrants as gifted 
with the power of mutual communication by articulate sounds, 
without which how could so much harmony be conceived or works 
of art executed? From the sagacity of the swallow the glass- 
maker has received his best lesson for building his pots, a mat- 
ter not of the least consequence in that art. 
There is just now a new nest, built by the white-tailed swaliow 
a short time before their departure, which displavs more than 
ordinary wisdom and sagacity in the execution.» It is placed in 
the west corner of a window facing the south, and covers more 
than a fourth of the glass of that pane. The operations went on 
much in the usual style, till better than half built; when, instead 
of going forward with the work, and leaving the entrance thereto 
at the top as usual, they made a halt at that side next the glass, 
to which they were conscious their mortar could not have ad- 
hered with sufficient tenacity, and where the great burden of the 
nest must have rested. Thus the safety of the whole would have 
been endangered. The outside of the nest furthest from the glass 
was carried up the full height, closed in, and made good to the up- 
per lintel. Returning to the unfinished part, they carried up a pillar 
by the side of, and leaning to, the glass, upon which they formed 
a capital projecting outwards from the glass. On the opposite 
side, upon that part of the nest carried forward and completed, 
they formed a corresponding butment; between these they con- 
S 4 structed 
