Chillies contain capsaicin, which is the source of their fiery flavour. It is an oily substance, not water soluable, that can be painful in contact with eyes or other sensitive areas. Measured in Scoville units ranging from 0 to 300,000.
Nutmeg is the hard kernel of the fruit of an evergreen tree native to the Moluccas (Spice Islands). The fruit is split open to reveal the seed - nutmeg - which is wrapped in a bright red lacy covering - mace.