One section of the law expresses the fact that the weights of two substances, not necessarily elements, that are equivalent in one reaction, are often found to be equivalent in a number of other reactions.
Such a system of classification, although convenient, is not the most natural one, and a sketch of the system which better expresses the relationships between the various subdivisions is given here.
The quality which Geoffrey Malaterra expresses by the word "effrenatissima" is also clearly marked in Norman history.
Equation (3), § I expresses the fundamental condition which must be satisfied when a locomotive is starting a train.
In all countries passenger trains must vary in weight according to the different services they have to perform; suburban Weight trains, for example, meant to hold as many pas ah d sengers as possible, and travelling at low speeds, do not weigh so much as long-distance expresses, which include dining and sleeping cars, and on which, from considerations of comfort, more space must be allowed each occupant.