(1) The Grand Canal, comes with Engineering. Must be built in a city with access to fresh water. You can connect the city square by a canal to any other square within distance 10, provided that square also has access to fresh water. You do this by choosing the originating and terminating vertices, and vertices in between if there's more than possible route, although the canal must be as straight as possible. (If you do it diagonally the straighest route is a zigzag.)
The canal acts as an artificial river. All land squares bordering it get the commerce bonus, and all squares except for mountain squares get the irrigation bonus as well. (In other words, hills, forest, tundra and jungles also get +1 food.) Squares which are already irrigated do not get a second bonus.
(2) The Imperial Zoo, great wonder produced by education(?). Produces +2 happiness in the cityand +1 happiness in all cites greater than size six. No happiness bonus for towns of size 1-6 since they're too small to have a decent local zoo.
In addition, your zoo produces one white elephant per age for every civilization, maximum eight per age. You may give an elephant to any civilization you are at peace with. They are compelled to accept the white elephant. They pay five gold pieces per turn to maintain the elephant for 20 turns, or until they or you enter into the next age, at which point the elephant expires. During this time the civilization receiving the elephant cannot declare war on you. You cannot give a white elephant to a civilization which already has a living elephant, or on the turn the elephant dies. (This is to keep you from keeping another civilization perpetually at peace.) At the beginning of the next age, you are restored to your full complement of elephants. It does not cost you anything to maintain your own elephants.
Any civilization which receives a white elephant may attempt to trade it to any civilization which does not have one, excluding the one which possesses the wonder. (He doesn't need another.) In that case the receiving civilization pays the upkeep, and the two civilizations stay at peace for the rest of the elephants 20 turn life. Note that since the first civilization no longer has a white elephant, the person with the Wonder can give him another.
In the moden age, you can replace the elephants with pandas.