[R] newbie polr() question

[Max]

Hi everyone, I'm trying to understand some R output here for ordinal 
regression. I have some integer data called "A" split up into 3 ordinal 
categories, top, middle and bottom, T, M and B respectively.

I have to explain this output to people who have a very poor idea about 
statistics and just need to make sure I know what I'm talking about 
first.

Here's the output:

Call:
polr(formula = Factor ~ A, data = a, Hess = TRUE, method = "logistic")

Coefficients:
Value        Std. Error  t value
A -0.1259028 0.04758539  -2.645829

Intercepts:
Value Std. Error t value
B|M -2.5872 0.5596 -4.6232
M|T 0.3044 0.4864 0.6258

Residual Deviance: 204.8798
AIC: 210.8798

I really am not sure what the intercepts mean at all. However, my 
understanding of the coefficient of A is that as the category 
increases, A decreases? If I have an A value of 10, how to I figure out 
the estimated probability that this score is in one of the three 
categories?

thanks!