From these formulae we derive two important relations, dp4 = or the function F, on the right which multiplies r, is said to be a simultaneous invariant or covariant of the system of quantics.
It forms extensive woods in Russia, but does not extend to Scandinavia, where its absence is somewhat remarkable, as the tree grows freely in Norway and Sweden where planted, and even multiplies itself by self-sown seed, according to F.
The Metazoa all commence their individual existence as a single cell or plastid, which multiplies itself by transverse division.
The report also considers it proved that the bacillus pestis multiplies in the stomach of a flea and may remain a considerable time within its host.
As human intelligence and industry come into play the means of livelihood are proportionately extended; population multiplies, and with this multiplication production increases.