The number is certainly the cause.
The apparent disorder augments the grandeur, for the appearance of care is highly contrary to our ideas of magnificence.

Besides, the stars lie in such apparent confusion, as makes it impossible on ordinary occasions to reckon them.

This gives them the advantage of a sort of infinity.

In works of art, this kind of grandeur which consists in multitude, is to be very cautiously admitted; because a profusion of excellent things is not to be attained, or with too much difficulty; and because in many cases this splendid confusion would destroy all use, which should be attended to in most of the works of art with the greatest care; besides, it is to be considered, that unless you can produce an appearance of infinity by your disorder, you will have disorder only without magnificence.

There are, however, a sort of fireworks, and some other things, that in this way succeed well, and are truly grand.