senescence being:

Have I a body or have I none?
Am I who I am or am I not?
Pondering these questions,
I sit leaning against the cliff while the
                        years go by.
Till the green grass grows between my feet
And the red dust settles on my head,
And the men of the world, thinking me dead,
Come with offerings of wine and fruit
                        to lay by my corpse.
Han-shan. From, Cold Mountain.
B. Watson, Translator. New York, 1970

tallow lamps: "Nothing is more destructive of the true values of primeval art than the glare of electric light in this realm of eternal night. Flares or small stone lamps burning animal fat, of which examples have been found, permit one to obtain only fragmentary glimpses of the colors and lines of the objects depicted. In such a soft, flickering light these take on an almost magical movement."
S. Giedion, "Space Conception in Prehistoric Art." In, E. Carpenter and M. McLuhan, Editors, Explorations In Communication. Boston, MA., 1960. p. 79.

eccos: "I call God ECCO now. The Earth Coincidence Control Office. It's much more satisfying to call it that. A lot of people accept this and they don't know that they're just talking about God. I finally found a God that was big enough. As the astronomer said to the Minister, 'My God's astronomical.' The Minister said, 'How can you relate to something so big?' The astronomer said, 'Well, that isn't the problem. Your God's too small.'" J. Lilly, "From Here to Alternity." In, D.J. Brown & R.M. Novick, Interviewers. Mavericks Of The Mind. Freedom, CA., 1993. p.206.

acoustics: "It has been previously observed that the shape of the cave exerted some general influence on the placement of species (on the walls). Indeed, shape is one major determinant of cave acoustics. However, the highly sound-reflecting axial gallery decorated with ungulates and the acoustically dead chamber of felines in the same cave of Lascaux are both narrow dead-end tunnels, suggesting that the cave shape was influential only to the extent that it does affect the acoustics." S.J. Walter, "Sound and Rock Art." Nature. 10 June 1993. p.501.