The first constructor of reflecting telescopes on a large scale, William Herschel, never published anything about his methods of casting and polishing specula, and he does not appear to have been very successful beyond specula of 18 in.
The great calculating engine was never completed; the constructor apparently desired to adopt a new principle when the first specimen was nearly complete, to make it not a difference but an analytical engine, and the government declined to accept the further risk (see Calculating Machines).
Wolfius infers from this passage that its author was the first actual constructor of a telescope, and it appears not improbable that by happy accident Porta really did make some primitive form of telescope which excited the wonder of his friends.
Consequently the Gaussian theory only supplies a convenient method of approximating to reality; and no constructor would attempt to realize this unattainable ideal.
The identification with Ancus is shown by the legend which makes the latter a bridge-builder (pontifex), the constructor of the first wooden bridge over the Tiber.
Although planned in the shape of a cross, with a square and tower in the middle, the arms of the cross are not straight, the constructor holding the ingenious opinion that, in order to prevent little towns from being taken in at a glance, their streets should be crooked.
Of Rome, founded, no doubt, by the original constructor of the road.
This consideration should be carefully, remembered in the future by the planter who may require an evaporator and by the engineer who may be called upon to design or construct it, and more especially by a constructor without practical experience of the working of his constructions.
In these circumstances the constructor has two broad alternatives between which to choose.
He is always associated with his brother Trophonius as a wonderful architect, the constructor of underground shrines and grottos for the reception of hidden treasure.