🚀 go-pugleaf

I am using the following settings in the preamble of my thesis:
%
\setlength{\marginparwidth}{0pt}
\setlength{\oddsidemargin}{0pt}
\setlength{\evensidemargin}{0pt}
\setlength{\marginparsep}{0pt}
\setlength{\topmargin}{0pt}
\setlength{\textwidth}{6in}
\setlength{\hoffset}{0.5in}% Shift 0.5in to the right
\setlength{\topmargin}{0pt}
\setlength{\headheight}{0pt}
\setlength{\headsep}{0pt}
\setlength{\textheight}{8.9in}% Just like Plain TeX
%
because I want the left margin to be 1.5in and the rest of the margins to be
1in exact. However it turns out the top margin is not exactly 1 inch. Its
height is about 1in + approximately 1 baselineskip. 

My question is why I cannot get the top margin to be 1 inch exactly.
How can I remove that extra space?

Thanks in advance.

Jesse Lee
jesse@cs.ualberta.ca

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Jesse Lee			  | UUCP:       jesse@alberta.uucp
Department of Computing Science   | Internet:   jesse@cs.ualberta.ca
University of Alberta             | CompuServe: 72531,3641
Edmonton, Alberta 
Canada T6G 2H1
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