After so much clinical observation Dr. Thomas.C.Duncan classified Electro- negative and Electro- positive remedies for two different group of children suffering fromexcessive acid or excessive alkali in the system….

“I desire to communicate to the practitioners of our school a rule which I have followed with more and more confidence for the last ten years, and which I wish to have more extensively and fully tried.

[I acknowledge, as “practitioners of our school,” such only as are accustomed to observe the general practical rules laid down in the Organon, i.e., those which require the most careful inquiry into the symptoms of each case as a case by itself; the writing down of all the symptoms; the selecting of one remedy according to the characteristic similarity, and the administering of that one in the smallest doses and at the longest intervals the case allows.]

“The rule I propose to give may not answer for cases in which this course is not pursued, or only in some instances. I do not know, but in those cases in which I have preferred the lowest preparations, frequently repeated, I have found it of the same utility as in others.

“It is further to be remarked that this rule is only a subordinate one, the main rules never being altered by it, and that it is thus subject to apparent exceptions and modifications.”

Rule. Morning aggravation of a looseness of the bowels indicates the acids or electro-negative drugs. Evening aggravation of the same (diarrhoea) indicates the alkalies or electro-positive drugs; with coughs the reverse in the case. An aggravation in the morning indicates the alkalies. If in the evening the acids.

The looseness of the bowels, as well as cough, should be what is called `active.’ If they form a very subordinate group among the symptoms, the rule cannot be applied with the same certainty.

By “morning” I understand the hours from midnight until noon; by “evening” the hours from noon till midnight.

For the purpose of bringing into view all our medicines which belong to these two classes, I add a table containing all hitherto proved, including also some which have not yet been published, though proved by myself and friends.



Nitric acid,


Muriatic acid,



Fluoric acid,


Sulphuric acid,



Phosphoric acid,


Antimonium crudum,




Oxalic acid,

Citric acid,

Lactic acid,

Benzoic acid,


–Osmium. Electro-Positive. Hydrogen,



Kali carbonicum,

Natrum carbonicum

Lithium carbonicum




Magnesia carbonicum















—Petroleum, etc.

Those substances which are preceded by the sign (–) are such as may act in an opposite way. All such as readily form gaseous compounds with hydrogen may act like the alkalies. I observed this long ago with Sulphur, and a few weeks ago with Tellurium; it may be the same with Selenium, Arsenicum metallicum, Bismuthum metallicum, and Antimonium metallicum.

The combinations of Hydrogen with Chlorine, Bromine, Iodine, and Fluorine act electro-negatively.

The alkalies we have proved as carbonates, and it would be of very little use to prove them in their caustic state, as either another combination is formed with vehicles or they unite with carbonic acid while on the tongue or on their way down to the stomach. That they become free from chemical affinities in the potentized state has not yet been sufficiently proved to be adopted as a rule.

The heavier metals are only mentioned provisionally, as we shall consider them separately hereafter; and the iron group seems to incline to the other side.In fact, here, as well as everywhere else in nature, there are links between the extremes.

Plants and animals used as drugs always present combinations of alkalies or acids, and the application of the rule must be modified or restricted according to the prevalence of positive or negative action.

In the course of my lectures on Materia Medica in Allentown, I stated to the students that such of our drugs as belonged to the same family–as, for instance, the Solanaceae–were connected by a rule of relationship, in regard to their polarity of action, Capsicum being the electro-negative extreme and Tabacum the positive, the others standing in a regular order between. Among the Ranunculaceae the positive end is occupied by Helleborus, the negative by Staphysagria. This I find holds good in every family of plants and in every family of chemical substances; and we may from this conclude that the different plants also may be arranged in two classes according to their respective chemical constituents. There seems to be a correspondence between such families as are remarkable for containing acrid substances, as the Ranunculaceae and Euphorbiaceae, and the electro-negative chemicals, and between such families as contain bitter and narcotic substances and the electro-positive chemicals. In accordance with this remark I subjoin a small table of plants, as far as I think the rule holds good :

Thomas C. Duncan
Thomas C.Duncan, M.D., Ph.D., LL.D. Consulting Physician to the Chicago Foundlings' Home.
Editor of The United States Medical Investigator. Member of the Chicago Paedological Society. First President of the American Paedological Society Author of: Diseases of infants and children, with their homoeopathic treatment. Published 1878 and Hand book on the diseases of the heart and their homeopathic treatment. by Thomas C. Duncan, M.D. Published 1898