Two Interesting Facts
1. A freemartin is a sterile female cow. It arises because she shares a womb with a twin brother. The membranes that surround them fuse sometime during gestation and their blood supplies mix. This brings hormones and cells from the immune system in contact with each other so that the female becomes male; but not, interestingly, the other way around. They can also take each other's skin grafts.
2. Going 'on the wagon' meaning refraining from taking alcoholic drink arises from the last wagon ride made by condemned prisoners from the prison in Newgate to the gallows at Tyburn. By tradition the convicts were allowed into a tavern for a last drink while the driver stayed behind 'on the wagon' and was not invited to inside to partake.
There was something else too, but I can't remember what it is. This is happening more and more frequently. Hodmandod Senior says it is due to lack of sleep. I hope he's right.