When you try to insert SVG elements inside a document, jQuery does not handle the SVG namespace, therefor they are not recognized by the browser and not render.

Only a tree with an <svg> element is properly handled. The following work as expected:

$('body').append('<svg width="100px" height="100px"><circle cx="50" cy="50" r="39" fill="red" /></svg>');

Unfortunately, if you try to insert a element outside of an explicit <svg> element, it fail. The following does not work as expected

$('svg').append('<circle cx="50" cy="50" r="40" fill="green" />');

A live example of that issue is available on jsFiddle : http://jsfiddle.net/rVMKR/