What an odd choice to use $Var like that.
Can you not put it in a JS file? If not, I added this
public function SomeSlider()
{
return '
<script type="text/javascript">
jQuery(document).ready(function ($) {
var _SlideshowTransitions = [{
$Duration: 600,
$Delay: 50,
}];
});
</script>';
}
to PageController and in any template call it with $SomeSlider.RAW and appears in the DOM fine.
Pretty dirty though…