306 
BIRD-LIFE. 
with mud. In the North there are members of the 
family which line their nests with feathers. 
The nests of any of the birds already mentioned have 
no pretentions whatever to be called works of art, and are 
all far inferior to those we are about to name. These 
are not only perfect in all particulars hitherto mentioned, 
but show such art as is beyond the reach even of human 
hands : they may he divided into two classes of artificers, 
•—plasterers and weavers ; and both stick their materials 
together with a glutinous saliva. 
The lowest grade of plasterers are to be met with 
amongst the Thrush tribe. These coat the lower layer of 
the nest with mud, upon which they stick their neatly- 
finished lining of dry bents, roots, or leaves. The Song 
Thrush is, however, an exception, for it plasters the 
inside lining with tempered clay and mud, intermingled 
with touch-wood or small pieces of wet moss, the 
whole being worked to a smooth regular surface. The 
Nuthatch shows still greater science in the manipulation 
of mud and clay. It cleverly makes use of the holes made 
by Mr. Woodpecker, but is obliged to narrow the door¬ 
way, so as to keep out uninvited guests. To effect this 
it plasters up the edge of the entrance-hole with a wall 
of clay, often two inches thick, which becomes so hard 
as to defy the efforts of aught other than the original 
owner of the hole to break it down. A cousin of this 
charming little climbing-bird, the Syrian Nuthatch (Sitta 
syriaca ), does more, for it plasters its nest to the side 
of the rock, much after the fashion of the House Martin. 
This bird is, however, surpassed by an allied family, the 
Oven Builders ( Furnarius ) of South America, well known 
for their skill as plasterers: their nest is an astonishing 
piece of work. It is generally built on some good-sized 
