As Britain marks David Livingstone's 200th birthday (pictured here) on Tuesday (March 19), Christians are being reintroduced to one of the greatest missionaries and explorers of the 19th century.  Photo courtesy Wikimedia Commons/National Portrait Gallery in London

As Britain marks David Livingstone’s 200th birthday (pictured here) on Tuesday (March 19), Christians are being reintroduced to one of the greatest missionaries and explorers of the 19th century. Photo courtesy Wikimedia Commons/National Portrait Gallery in London