I went to bed early but didn’t drop off to sleep until just after ten o’clock. I had set the alarm for four-thirty despite knowing that usually I lie awake waiting for it to go off! I wanted to take an early walk and set off just after five-thirty. The forecast had been for a cold night and fairly windy with it. Whenever the wind blows it makes things colder than the dry bulb indicates. It is all about evaporation. As an engineer one of my responsibilities was to ensure a comfortable working environment for the staff across the site. I had to maintain an ambient temperature of 21 deg C and a relative humidity of 50% both within set limits. I often used a whirling hygrometer which is a device resembling one of those rattles people often used at football matches many years ago. In the hygrometer are two mercury-filled thermometers one of which has the bulb inside a sock which is dipped in distilled water. As the device is rotated at speed it takes two temperatures, a dry bulb and a wet bulb temperature. The wet bulb would generally produce a lower temperature than the dry bulb due to the cooling effect caused by the evaporation of the wet sock. A reference chart would be used to find the relative humidity using the two temperatures. That by the way was a slight diversion to my post! It is interesting though as many folk wouldn’t know why the wind has a cooling effect, they just know it does.
There you see the device in the picture. Although I was well wrapped up the walk was bracing to say the least! I chose to walk my current route in a clockwise direction rather than the counter-clockwise direction I normally take which meant walking along the sea front with the wind in my face. I was certainly glad when I reached the point where I would turn inland and then back home with the wind behind me! It began to rain. It took some time to ‘thaw out’ on my return. How different from a couple of weeks ago when it was quite balmy. Now the rain was heavier and the morning looked miserable but after breakfast I did a little more work in the garage. This time cutting out the slot in the door edge in which to sit the new lock. It took me ages to do it because the door was on its hinges. I should have done it whilst it was held in the workbench the day before but of course I didn’t have it then. Suddenly I had it finished, the slot anyway and I stopped work. “I’ve had enough” I told myself and tidied up. It was twelve forty-five and time for lunch.