237. The reason why a spiritual angel draws out and elicits spiritual meanings from the literal sense of the Word, and a celestial angel celestial meanings, is that such meanings are in harmony with their nature and are of the same type as they are. This fact can be illustrated by similar facts in the three kingdoms of nature, the animal, vegetable and mineral kingdoms. In the animal kingdom, from food reduced to chyle the vessels of the body draw and extract the blood they need, the fibres of the nerves draw their liquid, and the substances from which the fibres originate draw their spirit. In the vegetable kingdom, a tree with its trunk, branches, leaves and fruits stands upon its root, and by means of the root draws out and extracts from the soil a thick sap for the trunk, the branches and leaves, a purer sap for the flesh of the fruits, and the purest for the seeds inside the fruits. In the mineral kingdom, there are in certain places hidden deep in the earth mineral ores rich in gold, silver, copper and iron; from exhalations and effluvia from the rocks gold attracts its own element, silver its, [copper its]* and iron its, and a solution circulates them.