194 THE LIFE OF A BIRD. 



In proof that this simple experiment of writing 

 upon eggs may sometimes be turned to dangerous 

 account, the following anecdote may be told. In 

 the month of August 1808, an egg was found upon 

 the altar of the Patriarchal church at Lisbon, 

 bearing upon its shell the sentence of death of all 

 the French, although there did not appear to be 

 traces of the writing being the production of the 

 hand of man. This apparent miracle caused much 

 anxious excitement among the Portuguese, until 

 the French distributed throughout the town, and 

 had placed in all the churches, an immense number 

 of eggs, upon the shells of which the contradic- 

 tion of this lie was written. At the same time 

 proclamations were everywhere posted up, ex- 

 plaining the secret of the supposed miracle, which 

 consisted in writing upon the shell, when covered 

 with an oily substance, and then plunging and 

 retaining the egg for some time in an acid. 



Until of late the structure of the egg-shell had 

 attracted but little notice, and it was generally 

 considered to be very simple ; the hard calcareous 

 part was thought to be simply a precipitate of 

 chemical substances, in some instances apparently 

 crystalline, in others not so, the particles of which 



