Gently plucking cactus thorns in the tropical dryhouse

On a cold snowy day it was a relief to enter the warm tropical house in the lovely Botanical Garden here. In the dry section there are many healthy looking cactii with sometimes tuneful thorns. The atmosphere is extremely quiet, the slightest sound, including ones own movements, make a noticeable impact. The contrast with the sound outside is heard when I leave the dryhouse at the end. Iconoclast composer John Cage liked the sounds of cactus spines and wrote pieces in which they are played, e.g. Child of Trees & Branches.