Can you explain the relationship between agriculture and the development of technology in Guns, Germs, and Steel?

The best place to find an answer to this question is
Chapter 13.  There, Diamond gives two reasons why agriculture leads to the development
of technology.

The first reason comes from the fact that
agriculture generally makes people stay in one place rather than roaming nomadically. 
When this happened, people could accumulate more possessions since they didn't have to
carry them everywhere with them.  They could then have more of a use for technologies
(Diamond gives the example of a loom) that were not
portable.

The second reason comes from the fact that
agriculture makes more food available.  Farmers can produce enough to feed themselves
and their families and still have a surplus.  This surplus
can feed specialists who can do things like creating and using
technology.

In these two ways, agriculture leads (Diamond
says) to the development of technology.