[R] as.matrix behaves weird

[Alexx Hardt]

Hi,
can someone tell me why x is still a 2x1-matrix in the last step?

 > x <- 1:2
 > x
[1] 1 2
 > t(x)
      [,1] [,2]
[1,]    1    2
 > x <- as.matrix(x,ncol=2)
 > x
      [,1]
[1,]    1
[2,]    2


I figured out that if I use "x <- matrix(x,ncol=2)", instead of 
as.matrix(), it works fine. What exactly is the difference between 
matrix() and as.matrix() here?
The help file describes the two functions with different words, but the 
essence sounds like the same to me.

Thanks in advance,
  Alex