This little tidbit includes for Soda Fountains as well as for home use:
Cream Soda, Using Cow's Cream, For Fountains.— Nice loaf sugar 5 lbs.; sweet rich cream 1 qt.; water 1 1/2gills; warm gradually so as not to burn; extract of vanilla 3/4 oz.; extract of nutmeg 1/4 oz.
Just bring to a boiling heat, for if you cook it any length of time it will crystalize; use four or five spoons of this syrup instead of three as in other syrups. If used without a fountain, tartaric acid one-quarter pound is added. The tendency of this syrup is to sour rather quicker than other syrups, but it is very nice while it lasts; and if only made in small quantities and kept cool, it more than pays for the trouble of making often.
Cream Soda, Without A Fountain.—Coffee sugar 4 lbs; water 3 pts.; nutmegs grated 3 in number; whites oi 10 eggs well beaten; gum arabic 1 oz.; oil of lemon 20 drops; or extract equal to that amount. By using oils of other fruits you can make as many flavors from this as you desire, or prefer.
Mix all and place over a gentle fire, and stir well about thirty minutes; remove from the fire, strain, and divide into two parts; into one-half put supercarbonate of soda eight ounces; and into the other half put six ounces tartaric acid; shake well, and when cold they are ready to use, by oouring three or four spoons, from both parts, into separate glasses which are one-third full of cool water; stir each and pour together, and you have as nice a glass of cream soda as was ever drank, which can also be drank at your leisure, as the gum and eggs hold the gas.
Source: Dr. Chase's Recipes ©1866