Lake Manitoba also affords opportunity for inland shipping.
A steam railway ferry connects it with the island railway on Riigen, and so with Sassnitz, whence a regular steamboat mail service affords communication with Trelleborg in Sweden.
This affords an example of a principle which had been stated by Hess in a very general form under the name of the Law of Constant Heat Sums - namely, that the thermal effect of a given chemical action is the same, independently of the character and number of the stages in which it takes place.
To obtain a larger heating surface than a pipe affords, radiators are connected with the pipes where desired, and the water passing through them warms the surrounding air.
As the deed was not destroyed, but is in existence now, it is to be presumed that the terms of it were, riot fulfilled; but the fact that such a contract should have been drawn up by Napier himself affords a singular illustration of the state of society and the kind of events in the midst of which logarithms had their birth.