Anatomical Observations on the Lungs

not infrequently, they are subdivided into two lobes, especially in humans, but in animals original: "brutis". Early modern scientists often used "brutes" to refer to non-human animals used in dissection. they are more numerous.

I have observed a more wondrous and deeper division; for the mass of the lungs is composed of almost infinite small lobules Malpighi is describing the secondary lobules of the lung—the smallest units of the lung that are surrounded by connective tissue., each enclosed by its own distinct membrane and provided with shared vessels. These are attached to the branches of the trachea original: "asperæ arteriæ". Literally the "rough artery," this was the standard anatomical term for the windpipe and bronchi before "trachea" became the sole term. The "roughness" refers to the rings of cartilage.. These lobules can be observed if a semi-inflated lung is held up against the rays of the sun or a light; for certain almost transparent interstices Gaps or spaces between tissues. will emerge. If you follow these with a slight incision, you will separate the lobules—which remain attached on both sides to the trachea and the vessels—and you will see them wrapped in their own proper membrane when air is breathed in through the windpipe. This membrane can be separated with a careful dissection, and it shines when held up to the light. However, you will happen to see these more clearly if the lungs are lightly boiled original: "elixatione". Boiling was a common technique in 17th-century anatomy to harden soft tissues and make the connective "webs" easier to see and peel apart. and a painstaking dissection of the gaps is performed.

You will see the shape of the lobules depicted Malpighi refers here to the copperplate illustrations at the end of his book, which were among the first to show the microscopic texture of the lungs.; I have not been able to fully represent their insertion and various positions, because they vary according to different requirements. Since the trachea, with its attached vessels, branches out like a tree in every direction, and these ramifications Branch-like structures. sometimes end at the outermost surface of the lungs (which must be flat and even) and sometimes at their extreme corners—or rather, since they must be properly joined with neighboring and surrounding branches to maintain the proper position, connection, equal capacity, and spacing—these lobules are therefore positioned in various ways. Sometimes they are joined to the trachea by their base, sometimes by a side, and sometimes by their tip. You will see the likeness of these processes at their ends sketched in the form of a cypress nut The cone of a cypress tree, used here as a visual metaphor for the bunched, textured shape of the lung's internal structures.; I have collected the principal and simpler ones, as far as was possible, somewhat obscurely in the final plates.

Beyond the lobules, things must be observed that are wrapped within them: they are not simply empty voids or trapped hollow spaces everywhere. Indeed, they contain many extended membranes, sometimes parallel to each other and sometimes angled, which extend not only from the outer surface of the lobules positioned at the sides, but also from the internal substance of the lobules themselves. Between these membranes run very many tiny vessels