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$\begin{figure} \par\includegraphics[width=17cm,clip]{9447fig1.eps}\end{figure}$ Figure 1: Total intensity spectra ( bottom) and magnetic field strengths ( top) for six sources of our sample. The magnetic field strength is determined from the measured Zeeman splitting using the current best value for the 6.7 GHz methanol maser splitting coefficient. The Zeeman splitting is derived using the ``running'' cross-correlation method (see text).
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In the text

$\begin{figure} \par\includegraphics[width=16cm,clip]{9447fig2.eps}\end{figure}$ Figure 2: Total intensity and circular polarization spectrum for G37.40+1.52 ( left) and G109.86+2.10 (Cepheus A; right). The thick solid line in the bottom panel is best fit fractional total power derivative to the circular polarization spectrum.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{9447fig3.eps}\end{figure}$ Figure 3: Magnetic field strength B in the massive star forming region Cepheus A measured from Zeeman measurements as a function of $n_{\rm H_2}$ , the number density of neutral hydrogen. The solid triangle indicates the methanol maser measurement from the Effelsberg observations, the number density is taken to be in the range typical of 6.7 GHz methanol masers (Cragg et al. 2005), but cannot be determined precisely without observations of additional transition lines. Also indicated are the H₂O maser measurements (solid dots; Vlemmings et al. 2006a), average OH maser measurement (solid square; Bartkiewicz et al. 2005), NH₃ measurement (open square; Garay et al. 1996) and recent dust polarization measurement (open triangle; Curran & Chrysostomou 2007). The error bars on the density of these data are taken from the respective publications. The solid line is the theoretical relation $B\propto n^{0.5}$ fixed to the OH maser measurement. The dashed line is the error weighted best fit line to the presented measurements (the individual H₂O maser measurements were averaged). Additionally, the boxes indicate the range of literature values for HI/non-masing OH, OH maser, methanol maser (this paper) and H₂O maser Zeeman splitting observations for other massive star formation regions.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{9447fig4.eps}\end{figure}$ Figure 4: Measured flux averaged 6.7 GHz methanol maser magnetic field strength vs. average 1.6 and 6 GHz OH maser magnetic field strengths for those sources where both are available. Most literature values were taken from the compilation of molecular cloud magnetic field measurements by Han & Zhang (2007).
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{9447fig5.eps}\end{figure}$ Figure 5: Magnetic field direction and strength along the line-of-sight derived from the methanol maser Zeeman splitting observations presented in this paper projected onto the Galactic plane. The solid dots are the observed star-forming region with kinematic distances from Pestalozzi et al. (2005). These are known to be highly uncertain. The length of the vectors is scaled with B_||. The approximate location of the spiral arms is indicated as taken from Taylor & Cordes (1993).
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In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{9447fig6.eps} \end{figure}$ Figure 6: Total intensity spectra ( bottom) and magnetic field strength ( top) for all the sources of our sample with significant Zeeman splitting detection. The magnetic field strength is determined from the measured Zeeman splitting using the current best value for the 6.7 GHz methanol maser splitting coefficient. The Zeeman splitting is derived using the ``running'' cross-correlation method (see Sect. 2.3).
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In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{9447fig7.eps} \end{figure}$ Figure 7: As Fig. 6.
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In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{9447fig8.eps} \end{figure}$ Figure 8: Total intensity spectra of the sources in our sample for which no significant Zeeman splitting was detected.
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In the text

$\begin{figure} \par\includegraphics[width=17cm,clip]{9447fig1.eps}\end{figure}$	Figure 1: Total intensity spectra ( bottom) and magnetic field strengths ( top) for six sources of our sample. The magnetic field strength is determined from the measured Zeeman splitting using the current best value for the 6.7 GHz methanol maser splitting coefficient. The Zeeman splitting is derived using the ``running'' cross-correlation method (see text).
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$\begin{figure} \par\includegraphics[width=16cm,clip]{9447fig2.eps}\end{figure}$	Figure 2: Total intensity and circular polarization spectrum for G37.40+1.52 ( left) and G109.86+2.10 (Cepheus A; right). The thick solid line in the bottom panel is best fit fractional total power derivative to the circular polarization spectrum.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{9447fig4.eps}\end{figure}$	Figure 4: Measured flux averaged 6.7 GHz methanol maser magnetic field strength vs. average 1.6 and 6 GHz OH maser magnetic field strengths for those sources where both are available. Most literature values were taken from the compilation of molecular cloud magnetic field measurements by Han & Zhang (2007).
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$\begin{figure} \par\includegraphics[width=16.5cm,clip]{9447fig7.eps} \end{figure}$	Figure 7: As Fig. 6.
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$\begin{figure} \par\includegraphics[width=16.5cm,clip]{9447fig8.eps} \end{figure}$	Figure 8: Total intensity spectra of the sources in our sample for which no significant Zeeman splitting was detected.
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