Hi Mila, What I am interested in is the conditions at or near the place where Titanic sank. Now at the time that Titanic sank Marengo was less than 150 miles away (fully half the distance you state she was), and by 4pm on the day of the sinking Marengo was passing only 46 miles due South of Titanic's crash site. In North Atlantic terms this is very near indeed (and at the right time). It is highly significant that throughout this area and time (and at no other time or place on her Atlantic crossing) Marengo reports bright stars and much refraction. You claim that I misled my readers by not spelling out how far away she was at the time of Titanic's sinking, but I say that I was educating my readers into the conditions present that night in the area where the Titanic sank. I also included a photograph of the log book itself, including the recorded position of the ship and the refraction references, so my readers could see the primary material for themselves. As for your point about that air temperatures being warmer than the water when Marengo gave her readings, they were in fact generally colder than the water, except at noon on the day of Titanic's collision (marked Inv. below). It is a myth that the air has to be at least about three degrees warmer than the sea at the point of observation to make superior mirage refraction effects visible, as the log book below demonstrates. Clearly they are looking across areas where the sea is much colder than the air. And as I mentioned in an earlier post, refraction effects can be present even when air and sea temperatures have equalised at the surface, provided a strong inversion is present (and near) in the air column above. The Titanic sank in part of a large area of the North Atlantic where the cold waters of the Labrador Current flow into and mingle with the warm water of the Gulf Stream. The below readings are taken right through that area and are testament to the visual effects caused when cold and warm waters meet. In particular, note that that the water temperature in Degrees F halves (from 60.2 to 33.5) at the moment when Marengo is directly south of Titanic's crash site (and the air temperature suddenly drops almost 10 Degrees F (as Lightoller noted on Titanic, as she entered the Labrador Current from the East). And what conditions do we see there: "Much refraction" and "Great refraction". This is important evidence for the conditions of visibility present at Titanic's crash site.