All this is true, but three readings instead of one for each pointing, much more figure-work in computation (especially if corrections have to be applied to the scale readings to reduce them to exact normal screw readings), are factors which involve a far greater expenditure of time than making a few additional turns of a screw in the process of measurement.
Much labour was bestowed by him upon facilitating the computation of the movements of the asteroids.
The population is not susceptible of accurate computation, but probably it has always been small.
This is evident in the case~ of such plants as have a body consisting of filaments or plates of cells, and is little less conspicuous in those whose mass is but small, though the cells are evidently capable of computation in three dimensions.
If we take a moderate computation the number of recent species may be taken at 10,000-11,000.1 Dr R.