I want replace a(or each) element(number) instead another element(number) in a class while running page.

I try as following code but doesn't word true, what do i do?

**DEMO:** <http://jsfiddle.net/yMnDt/>

```
<div class="myGrid">
    1
    <p>
    123145
</div>​

$(".myGrid").clone().find('1').replaceWith( "8" );

```

​