APPENDIX
Extract from “Treatise on Scurvy,” by James Lind, London, 1772.
(a) Recipe for preparing a stable orange or lemon juice. Let the squeezed juice of these fruits be well cleared from the pulp and purified by standing for some time; then poured off from the gross sediment; or, to have it still purer, it may be filtrated. Let it then be put into any clean open vessel of china or stone-ware, which should be wider at the top than bottom, so that there may be the largest surface above to favor the evaporation. For this purpose a china basin or punch-bowl is proper, and generally made in the form required; all earthen glazed vessels are unfit, as their glazing will be dissolved by the acid. Into this pour the purified juice, and put it into a pan of water, upon a clear fire. Let the water come almost to a boil, and continue nearly in that state (with the basin containing the juice in the middle of it) until the juice is found to be of the consistence of a thick syrup when cold. The slower the evaporation of the juice the better; and it will require at least twelve or fourteen hours continuance in the bath heat before it is reduced to a proper consistence.
It is then, when cold, to be corked up in a bottle for use. Two dozen good oranges, weighing five pounds four ounces, will yield one pound nine ounces and a half of pure juice; and when evaporated, there will remain about five ounces of rob, or extract; which in bulk will be equal to less than three ounces of water. So that thus the acid, and the virtues of twelve dozen lemons or oranges, may be put into a quart bottle, and preserved for several years.
I have now some extract of lemons which was made four years ago.
Those who intend this extract for making punch may infuse some of the fresh peel of the oranges or lemons into the spirit before it is used.
But for this purpose I find it is sufficient to add a very small quantity of the outer peel to the extract a little before it is taken off the fire, and there will be all that is requisite to make it entirely equal to the freshest fruit.
(b) How to preserve berries and other fruits for long periods. And it may be proper to acquaint them that most berries, and several fruits, when gathered two-thirds ripe on a dry day, while the sun shines, if put into earthen pots, or rather in dry bottles, well corked, and sealed up, so that no air or moisture can enter, will keep a long time, and at the end of a year, be as fresh as when new pulled.
(c) Method of preparing an antiscorbutic decoction from fir-tops, leaves, bark, etc. When the Swedes carried on a war against the Muscovites, almost all the soldiers of their army were destroyed by the scurvy, having putrid gums, rigid tendons, etc. But a stop was put to the progress of this disease by the advice of Erbenius, the King’s physician, with a simple decoction of fir-tops, by which the most deplorable cases were perfectly recovered, and the rest of the soldiers prevented from falling into it.
I am inclined to believe by the description given by Cartier of the ameda tree, with a decoction of the bark and leaves of which his men were so speedily recovered, that it was the large swampy American spruce tree.