Chalk It is formed in the sea by sub-microscopic plankton, which fall to the sea floor and are then consolidated and compressed during diagenesis into chalk rock. Most people first encounter the word "chalk" in school where it refers to blackboard chalk, which was originally made of mineral chalk, since it readily crumbles and leaves particles that stick loosely to rough surfaces, allowing it to make writing that can be readily erased. Blackboard chalk manufacture now may utilize mineral chalk, other mineral sources of calcium carbonate, or the mineral gypsum (calcium sulfate). While gypsum-based blackboard chalk is the lowest cost to
What Are Little Boys Made Of? Iona and Peter Opie, this first appears in a manuscript by the English poet Robert Southey (1774–1843), who added the stanzas other than the two below. Though it is not mentioned elsewhere in his works or papers, it is generally agreed to be by him. The relevant section in the version attributed to Southey was: <poem> What are little boys made of What are little boys made of Snips & snails & puppy dogs tails And such are little boys made of. What are little girls made of Sugar & spice & all things nice</poem> Extracts from the nursery rhyme