Laravel how to Query Rows by Column in Eloquent

In Laravel, I can get the rows from a selected column in MySQL by a Laravel query.

$data = DB::query('select engagements from csv2');

However, I wonder how can I write this using Eloquent?

$data = Model::get(array('engagements'));

For example if I only want to get the E-mail for a user;

$email = User::get(array('email'));