Next message: Fred Hebard: "Re: Dip of the horizon"
As I understand, the dip of the horizon is the
most important factor that limits the precision
of measuring altitudes. (I include refraction of
the horizon to this).
In the Russian navigation book I read in my youth,
a special device for measuring this dip was frequently
mentioned. It was called "naklonomer Kavraiskogo"
(phonetic transliteration). Kavraiskii is a name, apparently some
expert/inventor in navigation,
I see this name sometimes attached to
various
Russian devices. The word "naklonomer" has literal translation
"dipmeter".
I have no idea of what this device looked like, or on what
principle it worked. I've never seen it on e-bay, for example.
(First I thought that this is translated as "clinometer",
but then after having seen several "clinometers" on e-bay
I concluded that this is not so).
The book made an impression that measuring the dip with
"naklonomer" was more precise than using the dip tables.
The only principle I can imagine is some "bubble arrangement",
but I always wondered why did they have a separate device,
rather than the usual bubble attachment to the sextant.
Apparently this was something much more precise than the
usual bubble attachment to a sextant.
(I suppose the usual bubble attachment gives worse results
than the natural horizon under normal conditions.
On the other hand, the Russian book recommended to
"always check the dip with "naklonomer" whenever possible,
and to obtain high precision").
Did any analogous devise exist in the West?
How was it called then?
How did it work?
Alex.
