What does Madame Defarge say about dolls and birds in A Tale of Two Cities?Chapter 15 in Book the Second

Chapter XV of Book the Second of A Tale of Two
Cities finds the mender of roads escorted into the wineshop by Ernest Defarge
and introduced to Madame Defarge.  In the wineshop, there there has been more than
ordinary drinking, and drinking of a sour wine.  Defarge introduces the blue-capped
mender of roads as "Jacques," and he relates what he has seen on the road. He has seen
the Marquis's carriage pass by with a man hanging onto the bottom of the carriage.  This
man had escaped when the Marquis called for him, but he has been "unluckily" found.  The
guards force him along as he is bound and has become lame.  When he falls the guards
laugh; all the village whispers by the fountain. 

As the
mender of roads passes the prison, he sees the man; he  regards the mender "like a dead
man."  As Defarge and the other Jacques listen, they assume the air of a tribunal as the
mender continues.  He tells them that there was a petition for the man's life; the
mender says that the petition is presented to the King himself.  But, the men at the
fountain whisper that the prisoner will be executed as having committed patricide, and
he receives a torturous death as his arm is torn from him and he has lost both legs. 
Finally, in the morning the prisoner hangs from a gallows over the water, poisoning it. 
After this story has been told, the Jacques put their heads together:  "To be registered
as doomed to destruction...the chateau and all the race."  The Evremonde family is of
interest to Mme. Defarge. 

On the following day, the King
and Queen pass by on the road, and there is much fanfare played. When the mender of
roads is so taken by their jewels and siliks and splendour that he cheers.  Wondering if
he has failed in the eyes of the Defarges, he asks  if he has made a mistake.  Defarge
tells him that he is the kind they want to deceive the aristocrats so they will suspect
nothing when the time comes. Mme. Defarge tells him that if he were to set upon a heap
of dolls, he would pick the finest, would he not?  And, she asks him if
he

"were shown
a flock of birds, unable to fly, and were set upon them to strip them of their feather
for your own advantage, you would set upon the finest feathers; would you
not?"

Today, Mme. Defarge
continues the metaphor, he has seen both dolls and birds. Soon, the revolutionaries will
"set upon" and "pluck" these dolls and birds, the aristocrats. And, it will be the time
of the Jacques to hand their own victims, just as the poor peasant has been
hung.