Uncleftish Beholding (1989) is a short text written by Poul Anderson. It is written using almost exclusively words of Germanic origin, and was intended to illustrate what the English language might look like if it had not received its considerable number of loanwords from other languages, particularly Latin, Greek and French.
The text is about basic atomic theory and relies on a number of word coinings, many of which have analogues in modern German. The title "uncleftish beholding" calques "atomic theory". The text begins:
It goes on to define "firststuffs" (chemical elements), such as "waterstuff" (hydrogen), "sourstuff" (oxygen), and "ymirstuff" (uranium), and "bulkbits" (molecules), "bindings" (compounds), and several other terms important to "uncleftish worldken" (atomic physics). ("Wasserstoff" and "Sauerstoff" are the modern German words for hydrogen and oxygen, and in Dutch the modern equivalents are "Waterstof" and "Zuurstof". "Sunstuff", meaning Helium, refers to Helios, Greek god of the Sun. "Ymirstuff" references Ymir, a giant in Norse mythology comparable to Uranus in Greek mythology.)
The text does not completely derive from the vocabulary of the Anglo-Saxons: it uses 'around' and 'round' in several cases. This may have been an accident, but since English has no surviving descendants or relicts of ymbe (cognate to German um), Anderson may have realized that his only alternative to this Romance loan was laborious circumlocution. And "stuff" itself is from Old French (albeit of ultimately Frankish origin).
In addition to these few deviations from its linguistic purpose, the composition also contains one scientific inaccuracy, in claiming that helium-4 is the only stable isotope (neglecting helium-3). Apart from this, it translates word-for-word into a sound exposition of the first few principles of atomic theory.
The text gained increased exposure and popularity when circulated around the Internet, and has served as inspiration for some inventors of Germanic English conlangs. Douglas Hofstadter, in discussing the piece in his book Le Ton beau de Marot, jocularly refers to the use of only Germanic roots for scientific pieces as "Ander-Saxon."