you pick it up and...
IT'S A WOLF'S UPPER JAW
It really must be the 17th century!
You've found a high register warm up!
These warm ups are for exercising the high/middle registers of your voice. They will make it easier to soar like a graceful goose over top notes. We’d recommend incorporating these exercises near the end of your warm-up session, to avoid straining your vocal cords.
HIGH REGISTER WARM UP
Think of a very soft sound, like puppies making their first whimpering noises. With closed lips, imitate this type of sound; a gentle hum, falling off the lips into a downwards slide.
Repeat this exercise, exploring the starting and stopping points within your high register, and feeling where the resonance sits.
When you are comfortable with this movement, move the hum down as normal, and then bring it back up, making a ‘pitch circle’ where you explore a few notes on either side of your hum. This helps with resonance and pitch stability in your upper range.
Repeat your pitch circle, ascending in pitch each time, stopping as soon as it becomes uncomfortable or tense.
NOTE! USE CARE!
Your high register should be warmed up very carefully, softly, and slowly, as to prevent strain or damage on/to the throat. Dynamically, these warm ups should be sung between very quietly and mostly quietly, the aim being to gently allow the voice to move higher without pushing or forcing it.