Seeking George William Newman of Wo Tshire

George William NEWMAN was in Victoria Australia by 1855.
His marriage Cert shows Father as Joseph Newman, a clerk; Mother Mary. His age in 1855 was 29. On at least 7 of his children's Birth Cert. show his birth place as Salisbury, one as Fisherton.
Have not found date or method of arrival in Aust., nor any match in Salisbury records on WEB.