9920. 'On its hem round about' means in the most external parts, where the natural is, in every direction. This is clear from the meaning of 'hem' as the most external parts, where the natural is, dealt with above in 9917; and from the meaning of 'round about' as on every side. For when 'the hem' means the most external parts the whole circumference of the hem means all the most external part, consequently everywhere or in every direction there.