According to Loewinger, based on his study of the fixed Hebrew calendar, the 8th year in the 19-year Metonic cycle
should not be intercalated, as it is unnecessary.
The short (3 dots, rarely only 2 dots, very rarely 4 dots) horizontal parts of the nearly horizontal lines refer to eclipses that are separated by one Metonic cycle
This relation is that, to six places of decimals, the number of days in 19 tropical years is equal to the number of days in 235 lunar cycles and is known as the metonic cycle
Another may be to question why the Mishnaic calendar was observationally based, while the Babylonian calendar it supposedly derived from had already evolved into a calculated calendar based on the 19-year Metonic cycle
since the fifth century B.
6) Nineteen is not an arbitrary number; rather it may be a reference to the Metonic cycle
or period, which is defined by OED as `the cycle of 19 Julian years .
This September 27th, one Metonic cycle
later, a very similar total lunar eclipse will be widely seen during the evening throughout the Americas.
The 2005 annular eclipse in Madrid, Spain, was one Metonic cycle
from the 1986 eclipse.