How to fix ReferenceError: Can't find variable: jQuery/$

I know, there are a lot of questions like this, but they doesn't help me.

My situation is following.

1. I copy one (working) site with some changes to create another.


2. After I did it with not so much changes javascript on new site doesn't work, saying "ReferenceError: Can't find variable: jQuery" and "ReferenceError: Can't find variable: $".


3. 
   

   I added into the code alerts:

   
   

   
   alert('aaa');
   var x=$('td[type="x"]').size();
   alert('aaa1');
   
   

and see "aaa" alert, but don't see "aaa".

4. 
   

   I've checked, like it is said here, with Safari's debugger that jquery files are found and loaded, I can see them in "Resources" tab.

   
   


5. 
   

   adding ready in the line doesn't help:

   
   

   
   alert('aaa');
   var x=$(document).ready($('td[type="x"]').size());
   alert('aaa1');
   
   

   
   
   
   
   6. I belive the jquery was included before using it, my code looks like this:
   
   
   
   

<... HTML>
        <script src="{$JS_DIR}/jquery/jquery-ui-1.8.6.custom.min.js?{$JS_VERSION}" language="javascript" type="text/javascript"></script>
        <... OTHER JS includes>
        {literal}
<script type="text/javascript">
    <... other functions>

        function XX() {
        alert('aaa');
                var X=$(document).ready($('td[type="x"]').size());
                alert('aaa1');
    <... other functions>
</script>
{/literal}
<EOF>

What else I can do about it?

I have OSX 10.10.3 and Safari 8.0.5.