Spring 2015

Caroline Marris, Stephanie Pope, Powder for Hourglasses, field notes

<title id="p010r_a5">Powder for hourglasses</title>

<ab id="p010r_b5">It must be made very fine and not subject to rust and with enough weight to flow. Taking i lb. [217] of lead, melt it and skim and purify it from its filth, then pour into it four ? of finely ground common salt, and take care that there are no stones or earth. And immediately after pouring it, stir continuously very well with an iron [tool] until the lead and salt are quite incorporated, and take it immediately off the fire, stirring continuously. And if it seems too coarse, grind it on a marble slab and pass it through a fine sieve then wash it as many as times as necessary until the water runs clear, throwing out the fine powder that will float on it, renewing the water as many times as necessary until it is completely cleared.</ab>

What historical question are we hoping to answer? :

Ingredients/Tools:

• 1 pound of lead (!)
• ‘ground common salt’
• Marble slab to grind on
• Fine sieve

Relevant recipes:

A bit diffuse – ‘powder’ is obviously mentioned dozens and dozens of times, with the overall impression being that the finest/smallest powders are the best.

No other mentions of ‘hourglass’ in the manuscript.

What sort of iron tool?

Procedure by which to treat the melted lead sounds pretty straightforward.

Other (sort-of) contemporary recipes:

First recipe for hourglass sand appears in a French household treatise named The Goodman of Paris, written between 1392 and 1394 by the Menagier de Paris as an instruction manual for his wife. The translated recipe is as follows:

"Take the grease which comes from the sawdust of marble when those great tombs of black marble be sawn, then boil it well in wine like a piece of meat and skim it, and then set it out to dry in the sun; and boil, skim and dry nine times; and thus it will be good."

The nine boilings, skimmings, and drying demanded by the recipe suggests that a very fine, purified powder is required for hourglass sand.

Relevant historical information

By the end of the 1300s, the making of hourglass sand was considered to be a routine household procedure.

Recipes from the 17th century also indicate that hourglass sand could be made from pulverize eggshells and plumbago – how well would these substances function as hourglass sand compared to the lead/salt recipe in our ms?

PROTOCOL – P010 POWDER FOR HOURGLASSES

Ingredients: lead, rock salt

1. Make sure there are no stones or earth in your rock salt.
2. Finely grind the rock salt (pass it through a sieve).
3. Melt 1lb lead in a crucible. Once it is melted, continue to heat the crucible itself.
4. Skim off the ‘filth’ or dross from the lead. You can use the paper method to test heat & draw off the scum.
5. Put your ground salt into the molten metal. Stir continuously with an ‘iron tool’ or metal rod until the metal and salt are well incorporated. There is no exact measurement of how much salt to use in the manuscript; best guess is that the metal should become grainy.
6. Once the two ingredients are incorporated, take the metal off of the flame, continuing to stir until it cools and solidifies.
7. If the grains are too coarse to serve as a smooth-flowing sand, grind the hourglass sand again on a marble slab and pass it through a sieve until it is all as fine as possible. You can also wash it in water and re-sieve it to flush out any impure pieces; do this until the water ‘runs clear.’

HOWEVER MANY EXPERIMENTS DESIRED