Altar stone
In Exodus 20:25, this signifies truths formed from good, or good in form, to signifies that nothing of self-intelligence should be involved in its forming. (Apocalypse Explained 391[21, 21])
Rivers
'Rivers' or 'floods' signify temptations. 'Rivers' signify truths in abundance serving the rational self, and so, the understanding, for the purpose of doctrine and life.
In Isaiah 43:2, 'rivers' and 'waters' signify difficulties and falsities.
(Odkazy: Apocalypse Revealed 683)