I was wondering how far north lemons made it and how early in the 19th century could you find them when I came across these fun recipes for or using lemonade. Note the dates of some of the sources. I did find an article written in 1801 comparing the use of crystalized lemon vs. real lemon juice.
In my research I did come across a note regarding the import of lemons from Spain and Madrid. Lemons and importing them had been going on before the 19th century.
white sugar 1lb.
tartaric acid 1/4 oz.
essence of lemon 30 drops
water 3 quarts
Source: The Cyclopedia of Practical Receipts ©1841
LEMONADE. To prepare lemonade a day before it is wanted for use, pare two dozen lemons as thin as possible. Put eight of the rinds into three quarts of hot water, not boiling, and cover it over for three or four hours. Rub some fine loaf sugar on the lemons to attract the essence, and put it into a china bowl, into which the juice of the lemons is to be squeezed. Add a pound and a half of fine sugar, then put the water to the above, and three quarts of boiling milk. Pour the mixture through a jelly bag, till it is perfectly clear.—Another way. Pare a quantity of lemons, and pour some hot water on the peels. While infusing, boil some sugar and water to a good syrup, with the white of an egg whipt up. When it boils, pour a little cold water into it. Set it on again, and when it boils take off the pan, and let it stand by to settle. If there be any scum, take it off, and pour it clear from the sediment, to the water in which the peels were infused, and the lemon juice. Stir and taste it, and add as much more water as shall be necessary to make a very rich lemonade. Wet a jelly bag, and squeeze it dry; then strain the liquor, and it will be very fine.—To make a lemonade which has the appearance of jelly, pare two Seville oranges and six lemons very thin, and steep them four hours in a quart of hot water. Boil a pound and a quarter of loaf sugar in three pints of water, aud skim it clean. Add the two liquors to the juice of six China oranges, and twelve lemons; stir the whole well, and run it through a jelly bag till it is ouite clear. Then add a little orange water, if approved, and more sugar if necessary. Let it be well corked, and it will keep.--Lemonade may be prepared in a minute, by pounding a quarter of an ounce of citric or crystalised lemon acid, with a few drops of quintessence of lemon peel, and mixing it by degrees with a pint of clarified syrup or capillaries.
Source: The Cook and Housekeeper's Complete and Universal Dictionary ©1822
Three lemons to a pint of water, makes strong lemonade ; sweeten to your taste.
This is the best beverage for parties, cool, refreshing, pleasant and salubrious.
Source: Good Housekeeper ©1839
LEMONADE ICED. Make a quart of rich lemonade, whip the whites of six fresh eggs to a strong froth—mix them well with the lemonade, and freeze it. The juice of morello cherries, or of currants mixed with water and sugar, and prepared in the same way, make very delicate ices.
Source: The Virginia Housewife ©1838