This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
The orange-flower water of commerce is usually prepared from the oil or essence of neroli. The best quality is that distilled with the orange flowers in preparing the oils; the second quality is that prepared with oil and water, and rectified by distillation; the third quality is that distilled with the leaves and unripe fruits in preparing the oil neroli petitgrain. For the carbonator's purpose the second quality is of importance, which he can prepare himself. In compounding beverages, it is principally employed, as an addition to lemon syrup, to enhance the bouquet and delicate flavor.
Formula L - Concentrated essence of neroli, eight ounces; distilled water, one gallon (or dissolve one drachm of the oil in some alcohol and add); pumice, powdered, two ounces. Mix together thoroughly by shaking, allow it to stand twelve hours and filter through filtering paper.
Concentrated essence of neroli, eight ounces; water, ten pints; pumice, powdered, two ounces; mix together and distil, until one gallon (eight pints) are received.
N.B. If no distilled water is used, distillation is necessary to refine the aroma, which is quite important.