\textheight 24.0cm %bottom margin is relative to top!
\textwidth 6.5in
\fontsize{12}{14}% I think this is superceded by the 12pt in the documentclass
%\parskip 5.mm
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% Try to disable hyphenation
\pretolerance=2000
\tolerance=3000
%try to use semicolons between in text citations instead of commas
\bibpunct{(}{)}{;}{(a}{}{}
%%%%%%%%%%%% set the harvard style used in text
%\citationmode{default}
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%Preventing figures from appearing on a page by themselves.
% LaTeX's figure placement algorithm is quite biased in favour of putting figures on a page by themselves, instead of on the top of a page with some text below it. Often, I find the result aesthetically unappealing (to be polite). Fortunately, the parameters of the algorithm can be changed. The main problem is that LaTeX per default only allows a part of the top of a text-page (70%) to contain figures, and requires at least 20% of a page to be text when text and figures share a page. These parameters should be set to more reasonable values, for example 85% and 10%.
\renewcommand{\topfraction}{0.85}
\renewcommand{\textfraction}{0.1}
% This helps, but sometimes LaTeX puts a figure on a page by itself, although it would fit perfectly well on the top of a page. This happens when the figure will not fit on the page where it was defined. LaTeX then attempts to put it on a figures-only page before it attempts to put it at the top of the next page. A page may contain figures alone if the figure(s) use at least half the page. To prevent half-empty pages this limit should probably be increased to around 75%.
\renewcommand{\floatpagefraction}{0.75}
% Be careful not to make \floatpagefraction larger than \topfraction, then you risk to produce a figure that can neither go on the top of a text page, nor on a page by itself. If that happens, the figure and all later figures will be postponed until next time a \clearpage is executed (typically at the end of a chapter or the end of the document). This will also happen if a figure is too large to fit on a page.