Originally, exactly as much as a volume of water equal to the cube of the hundredth part of the metre, at the temperature of melting ice. I don't find that terribly helpful. Not many did. That's why, in 1889, the mass of the kilogram was redefined as being equal to the IPK.
Boiling water is also an effective poison ivy killer. If the area where you will be killing poison ivy has no other plants you wish to keep, pour boiling water over the poison ivy plant. Boiling water will kill any part of a plant that it comes in contact with, so be careful using this around desirable plants.
Apply to the rash and let dry. Another tried-and-true method for many poison ivy sufferers is full immersion in a soothing baking soda bath by adding 1/2 cup of baking soda to the bath water. â¢ Hydrocortisone cream - the over-the-counter anti-itch cream also helps to reduce swelling.