One-third to be deducted off all repairs and renewals.
One-sixth to be deducted off chain cables.
The oxygen contained in the compound was deducted, together with the equivalent amount of hydrogen, and the heat of combustion of the compound was then taken to be equal to the heats of combustion of the elements in the residue.
From all differences interest at 5% is deducted for the time between settlement day and the tenth day of the second month on which the " future " elapses, since settlement terms mean that money is paid in instalments before it is actually due.
Passing now to the examination of the budget, it should be observed that the method of estimating the revenues - a matter of great difficulty owing to the previous want of method - is described by Laurent as follows: " For every nature of receipts the total effective collections for the five last known years were set out, the averages were taken of these and the increase or decrease of the yearly average of those same years was worked out and added to or deducted from the figure previously obtained.