This basically means that the libMagickWand.so.1 file cannot be found. However, it is available on your system. All you need to do to fix it, is tell your box to look in the right place for the file.
To fix this issue once and for all, open up /etc/ld.so.conf.d/whatever_file_is_here. The whatever_file_is_here is named after the kernel you have installed.
In this file, add the following line at the bottom
Save the file and next run the 'ldconfig' command. This will reread the configuration file you just edited. Now, restart your Rails app and you'll notice the error is gone and all is good again.