Receiving UK First Day covers in the mail once or twice a month from the Royal Mail is a passive form of collecting, I admit…..but the array of topics and creative art that often (but not always) is provided in these covers is astounding.  I have been collecting since October of 1993, and this ‘Sherlock Holmes” theme was my first received.  To view more samples go the pull down “Thematic Philately” Tab on the blog.