on an other board i frequent, a thread turned to a food thread-(honest, it wasn't me, and i haven't contributed to it..)
one question that came up was caster sugar

what is caster sugar? Apparently a what we in US would call superfine sugar (2X not 10X) not "confectionares sugar" (which is graded 10X) but finer than normal granualated sugar.
my question is, Why caster?
the america heritage defines caster (varient castor) as
1. One that casts: a caster of nets. 2. also cas·tor ( kstr) A small wheel on a swivel, attached under a piece of furniture or other heavy object to make it easier to move. 3. also castor a. A small bottle, pot, or shaker for holding a condiment. b. A stand for a set of condiment containers.

is caster sugar so named because it is found in 3.a? or is there an other reason for the name?

(we can follow up on niblet corn, or stingless beans, or burpless cucumbers... or even revive the thread, and talk about musk melons..) not that i am starting a food thread or anything!