milk.data <- read.table("milk.dat",skip=3,col.names=c("sample","lab","bacteria"))
attach(milk.data)

# postscript(file="milkplot1.ps")

par(mfrow=c(2,1)) # A 2x1 template (for two plots in a single column)

plot(x=sample,y=bacteria,pch=lab)
title("untransformed data")
legend(2.5,4400,pch=1:5,legend=c("Lab 1","Lab 2","Lab 3","Lab 4","Lab 5"))

plot(x=sample,y=log(bacteria),pch=lab)
title("log transformed data") 
# postscript()