@Balick2017 presented a detailed hydrodynamical model of OH 231.8+4.2 where they distinguished both lobes. The region coincident with our area “C” is represented with a faster ejection (400 km s$^{-1}$ against 225 km s$^{-1}$ for the northern lobe), a wider opening angle (50/ 30) and a higher injection mass rate (2.3e$^{-2}$ M$_{\odot}$ yr$^{-1}$ / 4.8e$^{-3}$ M$_{\odot}$ yr$^{-1}$). These conditions would therefore contribute to the explanation for the lack of organization in the distribution of vectors.

![image](Tower_sketch3-eps-converted-to.pdf){height="8cm"}

Global View of Magnetic Fields in OH 231.1+4.2 {#comp2}
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We can now use the new thermal dust polarization observations with existing OH maser data by @Etoka2009 and @Leal2012, to trace the magnetic field pattern from $\sim$30600 AU down to $\sim$40 AU from the central star (and by extrapolation to its surface).

Overall magnetic topology {#topology}
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The OH masers [@Etoka2009] and dust polarization emission data (SMA, ALMA) indicate the presence of a well organized magnetic field in the polar direction and in the “inner” parts of the nebula (i.e. the regions closer to the central star). The most spatially distant magnetic field lines seen with CARMA point towards the presence of an additional toroidal magnetic pattern. Such a dual distribution of the magnetic 