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An engineering paper from 1886 says,

"One of the tedious tasks that falls to the engineer of small cities is
that of making out time-tables, from year to year, for the lighting of
public lamps... I began at the bottom of the matter, and from a series
of experiments on the light afforded by twilight and the various phases
of the moon made out a schedule differing considerably from other tables
in common use... Some cities in public lighting take no cognizance of
moonlight, and street lamps blaze all night long; their flames look pale
enough, almost casting shadows in the bright light of a harvest moon.

"When the moon is full and half an hour up it shines between the houses
and trees as well as being somewhat reflected, furnishing light more
than the minimum limit. Next as to the least phase of the moon when its
light exceeds the limit and how high must it be. Our experiments proved
that the moon at one day larger than at 1/8 and two hours high will give
light in the streets to exceed the minimum.

In the gaslight era people apparently tolerated dark streets! The
author's times for lighting lamps (when moonlight is not a factor) are
at the beginning of nautical twilight. I'm sure most people nowadays
would consider it practically full night (dark enough for a firework
show) at -12° sun altitude.

Latitude and longitude are not stated for the tables in the article.
Furthermore, US railroads had adopted standard (zone) time only a few
years before. Some cities changed to standard time almost immediately,
but others did not. The article doesn't say anything on that.

I guessed 40N and the 90th meridian, the latter so local and zone times
would be identical. With latitude I got lucky. Sun set/rise time
discrepancies vs. the table occur if you go only one degree north or
south. However, the moon rise/set times fit a little better if you go
east to the 75th meridian.

Julius M. Howells, "A Revised Time Table for Lighting Public Lamps"
(Journal of the Association of Engineerig Secieties, April 1886). My URL
goes to the table of contents, since other articles in the volume my be
interesting.


https://www.google.com/books/edition/Journal_of_the_Association_of_Engineerin/rZcPAQAAIAAJ?hl=en&gbpv=1&pg=PP10&printsec=frontcover

--
Paul Hirose
sofajpl.com

   

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