I am working on a lab manual for a course that I teach. In the lab safety chapter, I want to have a table of the GHS pictograms and their descriptions. I plan for this to be a longtable so a page break can happen inside the table if needed. However, when I do this, I can only get the description text in the second column to align to the vertical center of the graphic (using an m column) or the bottom of the graphic (using either the p or b column). What is peculiar is that I get the same behavior with the graphic in either a p or b column. How do I get the the text in the second column to be aligned to to the top of the graphic or the top of the cell.
\documentclass{book}
\usepackage{longtable}
\usepackage{array}
\usepackage{graphicx}
\begin{document}
I expected this one to align the second column to the top of the graphic.
\begin{longtable}{|p{1in}| >{\raggedright}p{4.5in}|}\hline
p column & p column \tabularnewline \hline
\includegraphics[width=1in]{pictogram.png}
& This pictogram is for substances that have certain properties in certain situations.
This pictogram indicates a level and type of hazard or risk when using the substance.
\tabularnewline \hline
\end{longtable}
This one behaves like I expect.
\begin{longtable}{|m{1in}| >{\raggedright}p{4.5in}|}\hline
m column & p column \tabularnewline \hline
\includegraphics[width=1in]{pictogram.png}
& This pictogram is for substances that have certain properties in certain situations.
This pictogram indicates a level and type of hazard or risk when using the substance.
\tabularnewline \hline
\end{longtable}
This one behaves like I expect.
\begin{longtable}{|b{1in}| >{\raggedright}p{4.5in}|}\hline
b column & p column \tabularnewline \hline
\includegraphics[width=1in]{pictogram.png}
& This pictogram is for substances that have certain properties in certain situations.
This pictogram indicates a level and type of hazard or risk when using the substance.
\tabularnewline \hline
\end{longtable}
This one is close to what I want, but will not look correct with longer text.
\begin{longtable}{|m{1in}| >{\raggedright}b{4.5in}|}\hline
m column & b column \tabularnewline \hline
\includegraphics[width=1in]{pictogram.png}
& This pictogram is for substances that have certain properties in certain situations.
This pictogram indicates a level and type of hazard or risk when using the substance.
\tabularnewline \hline
\end{longtable}
\end{document}

