On the “Cosmic Egg” of the Puranas

 

The bronchial conduit is the cosmic egg of the Puranas 

Brahmanda Purana (1.1.1.43-44), while enumerating the topics, mentions the “golden cosmic egg” (andam hiranmayam) which had the “ocean” (vardhi) as its covering sheath (avarana). This egg is described as situated within the enclosure of the elements (bhutas) (45). Immediately after this (46), there is the mention of the “tree of Brahman” (brahma vrksa) and the birth of Brahma; this “tree” must be the “lotus” that grows forth from the navel of Visnu.

In the Vayu Purana, when Suta begins to relate the Purana, at the outset, he says that the ultimate cause is the Great Lord (mahesvara) and from him was born (1.44) the incomparable “golden cosmic egg” (andam hiranmayam); its covering sheath (avarana) was the “waters” (aḍbhi ?, āpas).

 

 It is not difficult to understand why the metaphor of the egg should be applied to the respiratory conduit. The bronchus has an exterior “shell” of (hyaline) cartilage which lends to it one of the properties or distinguishing characteristics of an egg. This cartilaginous layer provides patency to the bronchus and imparts to it hardness and a certain rigidity (or immoveable-ness," one of the defining features of a mountain); however, as one moves down the network of tubes, this layer is progressively lost and, ultimately, it disappears (at the level of the bronchioles).

And so, in this manner, there is a process of “unshelling,” “cracking” or “peeling” of this egg that goes on. The principal bronchus represents the original, undivided egg. As one moves down the bronchial tree, it is progressively “unpeeled.” At the level of the bronchioles, the egg is all “soft” and “light,” yolk-like as it were; as opposed to the upper portions of the tree which are “hard” and “heavy.”

The softer portions, especially the acinar zone, would be considered the "yolk" of this "cosmic egg."

Furthermore, we may have one other way of visualizing this cosmic egg. Instead of regarding the different levels of the bronchial tree as different states of the same egg, we may have a static conceptualization in which the entire respiratory tree is the egg. All the bronchi—the entities with “shell” (cartilage)—may collectively be referred to as the “shell;” while the remaining (non-cartilaginous) conduits may constitute the “yolk.”  

According to the Padma Purana, "Oceans with mountains and islands, the group of the worlds with the luminaries, all (this) along with gods, demons and human beings--was (present) in that egg."

The lungs were imagined by the ancient anatomists as containing the entire world, along with all its principal topographical entities. There was a translocation of the most extensive and exquisite kind. The pulmonary veins were imagined as oceans, the arteries as rivers and the (higher) bronchial conduits as mountains. The segments of the lungs were regarded as islands in view of their being bounded by the "oceans" (pulmonary veins). Like in the external world, this internal "earth" also is populated by "living beings." The neural entities are the "men" of the microcosm. 

According to the Kurma Purana, this "extensive cosmic egg" consists of fourteen parts.