title: RoR 4.2.0 Jquery not defined
body: <p>in my ror application i've a jquery error during the execution. On the Google Chrome Application appear this message </p>
  
  <blockquote>
    <p>Uncaught ReferenceError: jQuery is not defined</p>
  </blockquote>
  
  <p>this is my application.js:</p>
  
  <pre><code>// This is a manifest file that'll be compiled into application.js, which will include all the files
  // listed below.
  //
  // Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
  // or vendor/assets/javascripts of plugins, if any, can be referenced here using a relative path.
  //
  // It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
  // compiled file.
  //
  // Read Sprockets README (https://github.com/sstephenson/sprockets#sprockets-directives) for details
  // about supported directives.
  //
  //= require jquery
  //= require jquery_ujs
  //= require foundation
  //= require turbolinks
  //= require_tree .
  
  
  $(function(){ 
      $(document).foundation('alert'); 
  });
  </code></pre>
  
  <p>In the gemfile is present the jquery-rails gem.</p>
  
  <p>I really don't know where crush my head. All the help is appreciated</p>