They put some grain in these, and shook it up; one end of the yubbils being held much higher than the other, thus all the dust and dirt sifted to one end, whence it was blown off.

When the grain was sufficiently clean, it was put away in skin bags to be used as required, being then ground on the large flat dayoorl-stones, with a smaller flat stone held in both hands by the one grinding; this stone was rubbed up and down the dayoorl, grinding the seed on it, on which, from time to time, water was thrown to soften it.
When ground, the grain was made into little flat cakes, and cooked as the tree-seed cakes were.

When the harvesting of the yarmmara was done, a great hunt took place, a big feast was prepared, and a big corroboree held night after night for some time.
The two principal drinks were gullendoorie--that is, water sweetened with honey; and another made of the collarene, or flowers of the Coolabah (grey-leaved box), or Bibbil (poplar-leaved box) flowers, soaked all night in binguies (canoe-shaped wooden vessels) of water.
Just about Christmas time the collarene is at its best; and then, in the olden days, there were great feasts and corroborees held.
The flat dayoorl-stones on which the seeds are ground with the smaller stone, are like the 'saddle-stone querns' occasionally found in ancient British sites.

These primitive appliances preceded the circular rotatory querns in evolution, and as the monuments prove were used in ancient Egypt.

I cannot say whether, amongst the Euahlayi, there was a recognised licence as to exchange of wives on these festal occasions, or at boorahs.