From The Long Lost Friend:
A Wand For Searching For Iron Ore Or Water
On the first night of Christmas, between 11 and 12 o'clock, break off from any tree a young twig of one year's growth, in the three highest names (Father. Son. and Holy Ghost), at the same time facing toward sunrise. Whenever you apply this wand in searching for anything apply it three times. The twig must be forked, and each end of the fork must be held in one hand, so that the third and thickest part of it stands up, but do not hold it too tight. Strike the ground with the thickest end, and that which you desire will appear immediately, if there is any in the ground where you strike. The words to be spoken when the wand is thus applied are as follows:
Archangel Gabriel, I conjure thee in the name of God, the Almighty, to tell me, is there any water here or not? do tell me! + + +
If you are searching for Iron or Ore, you have to say the same, only mention the name of what you are searching for.
Timeline of related events
1820Publication of Hohmann's Long Lost Friend (lists this spell)