[R] use of split.screen() with postscript device

[Steven White]

Greetings,

I am new to R and quite confused by the apparent inconsistency in it's 
behavior. My latest difficulty lies in producing eps output for use with 
latex. In particular, I was successful in obtaining a single figure by using:

postscript("ripple1.eps",onefile=FALSE)
plot(nu_set[[1]],ip[[1]])
lines(nu_set[[1]],predict(fitIp[[1]]))
dev.off()

...but then I tried to place two figures on the same output sheet by using 
split.screen() as follows:

postscript("ripple1.eps",onefile=FALSE)
split.screen(c(1,2))
screen(1)
plot(nu_set[[1]],ip[[1]])
lines(nu_set[[1]],predict(fitIp[[1]]))
screen(2)
plot(rangeIpNorm)
dev.off()

and received no output whatsoever. Furthermore, I can no longer get postscript 
output using the original commands! I've tried exiting and re-starting R, and 
am just about to reboot because I almost cannot believe what I am seeing.

Can you spot anything that I am doing wrong?

Thanks & Best Regards,
Steve