This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
The performer produces a bottle and gives it with a glass to anyone in the audience, asking the person selected to take a drink of a very delicious concoction. When the person attempts to pour out the solution it is found to be frozen.
To perform this trick, the fluid must be previously made with a saturated solution of sulphate of soda and hot water. Fill a clean white bottle with the solution, taking care to cork the bottle while the liquid is hot. The liquid remains in a fluid state as long as the bottle is corked. When the bottle is shown, it appears to contair a liquid, and in handing it to a persor the performer must be careful to take out the cork in time to allow it tc solidify. In order to gain the proper time, pretend to be looking for a glass make some remark about a sudder chill or feel the hand holding the bottle and say it is very cold. In the mean time, the air acting upon the solution has caused it to become fixed and im movable, and when the person at tempts to pour it out, he finds it i: impossible.