Chinese infix -r-, as relevant to circles

Chinese infix -r-, as promised:
The following is taken mostly from
Sagart: The roots of Old Chinese

Abbreviations:
OC Old Chinese
MC Middle Chinese
(x) tone x

The treatment of reconstructed initial clusters
is complicated. *krV- eg. may result from
prefix *k&- plus root *rV- (fusing prefix)
root *kV- and infix *-r-

*k&-r- from *k&- plus root *rV- (iambic prefix)

example
root *lak "upper arm/leg"
yi4 OC *(b)lak > MC yek "armpit"
ge1 OC *(A)k-lak > MC kak
cf Cantonese k&-lak5/k&-la:k5 tai35 "armpit"
ge1 OC *(A)k-lak > MC kak
and OC *(A)kr-lak > MC kæk "hind-leg, haunch
(of sacrificial animal)"
luo4 OC *(A)k&-lak > MC lak "to fall, of tree leaves"
(cf Xiamen ka-lauh "fall"
Note Cantonese tai35 means "underside",
which means k&-lak5 means "joint" (my conclusion)

BTW
ba1 OC *(a)pra > MC pæ "boar" (in hunting contexts)
shi3 OC *(b)hlaj? > MC syeX "pig"
cf PIE *pork- and *su-


Torsten