NATURAL PRESUMPTIONS, evidence. Presumptions of fact; those which depend upon their own form and efficacy in generating belief or conviction in the mind, as derived from those connexions which are pointed out by experience; they are independent of any artificial connexions, and differ from mere presumptions of law in this essential respect, that the latter depend on and are a branch of th& particular system of jurisprudence to which they belong; but mere natural presumptions are derived wholly by means of the common experience of mankind, without the aid or control of any particular rule of law, but simply from the course of nature and the habits of society. These presumptions fall within the exclusive province of the jury, who are to pass upon the facts. 3 Bouv. Inst. n. 3064; Greenleaf on Ev. Sec. 44.