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+The jsroute sub-project allows us to use Google Maps from the command
+line. To do this, we require the env-js Javascript library. A remote
+reference, called a "submodule,"[1] has been created in the
+census-tools repository and points to env-js. To initialize/update it,
+run,
+
+ git submodule init
+ git submodule update
+
+Those two commands will initialize the submodule, and check it out
+within the lib/env-js directory. Now that env-js is present, you'll
+need to build it. There are some prerequisites for this; in
+particular, a Java runtime[2] and the Ant[3] build tool. If you are
+running Linux, I promise that both of these are available through your
+package manager.
+
+With the prerequisites installed, simply run 'make env-js' from within
+the 'lib' directory. This will change into the env-js directory, and
+run 'ant concat' which builds the library. With that complete, you can
+use jsroute.
+
+Just run ./jsroute from within this directory to display its usage.
+
+
+[1] http://book.git-scm.com/5_submodules.html
+[2] http://java.com/en/download/index.jsp
+[3] http://ant.apache.org/