In Anshutz's New Remedies you can find the original proving of Chionanthus virginica. For those new to homeopathic language, a proving is when a healthy person takes a dose of a medicine in order to understand the effects that medicine has on the body. Every remedy should be tested in this way before being given to patients. Many provings were done during Hahnemann's time (mid nineteenth century) and the original results have been lost; we only have access to secondary sources: compilations of of the original results with the intent to allow homeopaths to prescribe remedies based on the data.
Recently I went through the original proving of Chionanthus viriginica and I encourage others to do the same. The exercise raised more questions than it answered. How do you decide on time modalities? If someone wakes at 4am, is the symptom: worse at 4am OR is it because the prover took the tincture three hours previously? How many of the symptoms in this one proving characteristic (common and consistent) and how many are specific to this individual prover?
Our materia medica was put into perspective for me; it's a compilation of symptoms that are not as concrete and discreet as they seem. Additionally it became apparent that symptoms can only become concrete and discreet after many provings have been done.