Never look at the new moon through glass; always show it a coin and turn it over. English folk custom is full of very specific moon manners.

Bowing to the new crescent, turning silver in your pocket, and refusing to view it through a window were all common British and Irish practice into the twentieth century, the first sight of a new moon was a hinge point where luck could be set for the month. It's the same instinct as a new moon intention, with better props.