Maybe in the Victorian Era, were there spotlights? Could the lighting fade in and out?
In Kurt Froster's Stagecraft and Statecraft (Pg. 76) - Forster quotes famous 16th century stage director Leone de’Sommi as saying “Once I had to produce a tragedy, and, while the stage was brightly lit during the happy events, as soon as the first sorry accident occured- the unexpected death of a queen- and a chorus began to lament that sun could not bear to shine on such evil I contrived (in advance, of course) that at this instant most of the stage lights not used for the perspective were covered or extinguished: this caused a profound impression of horror among the spectators and was universally praised”.
This is bearing in mind that this was aided by advancements and opportunities allowed by having purpose-built indoor theater spaces as opposed to previously utilized catch-all spaces, or outdoor (often pop-up) venues. Namely that lighting as an integral part of the space was now being considered. The particular play to which de'Sommi was regarding took place in the Teatro all'antica in Sabbioneta - the first modern purpose-built theater.
In spaces like these you were less likely to see lights "fade in and out" as much as you were to see them "cut" out at various degrees in-order to achieve similar effects of dimmers. This would be one of the earlier instances of theatrical lighting to achieve effects.
As time passed you had more "technologically" advanced methods which would utilize mirrors and other shuttering methods (as opposed to just covering it) in order to restrict, amplify and even direct light.
This was more of an art than a science (heh), as if you begin to look at the history of spaces which housed theatrical productions through he years (particularly indoor venues) you'll see that a startling number of them no longer exist due to fires.
Hi, there's lots of room here for more / more in-depth info, but you can get started on a few comments here