Recently a guardsman H R Snow wrote to The Daily Telegraph on the subject of arranging books on a shelf. This was in reply to a previous correspondent who stated he arranges his books - tallest on the right and shortest on the left in military style. Mr Snow wrote: Speaking as a guardsman, my principle has always been: tallest on the flanks, shortest in the centre. This makes for a more pleasing visual display, whether of books or soldiers. During my time in uniform in the 1970s, whenever a parade was imminent we all lined up in single file, tallest on the left, shortest on the right. A right turn and then marched into ranks 1, 2, 3 1, 2, 3 etc. Obviously that meant all those on the left hand flank were taller than those on the right hand. Has this changed or is the above description by Mr Snow unique to the guards?