From the garage

this is a stud finder, necessary for all wooden constructions, if you want to  hang a painting on the wall or a tv.
And now my explanation about the fridge, I was reminded by Munni, that the German Carl von Linde invented in 1876 the first efficient compressed-ammonia refrigerator.
AND:
In 1922 the absorption refrigerator war invented by the Swedish inventors Baltzar von Platen and Carl Minters.
WE ARE ALWAYS LEARNING THRU BLIP!!!!!!!!!!!!!!!!!!!
I am sure there is a whole science behind all this, but I leave it at this.