A tune is an example of a non-uniform object.
We have perceived it as a whole in a certain duration; but the tune as a tune is not at any moment of that duration though one of the individual notes may be located there.
It is possible therefore that for the existence of certain sorts of objects, _e.g._ electrons, minimum quanta of time are requisite.

Some such postulate is apparently indicated by the modern quantum theory and it is perfectly consistent with the doctrine of objects maintained in these lectures.
Also the instance of the distinction between the electron as the mere quantitative electric charge of its situation and the electron as standing for the ingression of an object throughout nature illustrates the indefinite number of types of objects which exist in nature.

We can intellectually distinguish even subtler and subtler types of objects.
Here I reckon subtlety as meaning seclusion from the immediate apprehension of sense-awareness.

Evolution in the complexity of life means an increase in the types of objects directly sensed.

Delicacy of sense-apprehension means perceptions of objects as distinct entities which are mere subtle ideas to cruder sensibilities.