pwebb
Senior Retro Guru
When it comes to matters of what is straight or not, I usually make a trip to the Greenwich observatory to ensure that  any measuring devices are placed in  longitudinal alignment with the Meridian and  ideally  only when atmospheric pressure is  between 967 and 970 millibars  -  just to be sure there are  no  aberrations caused by geographical location or weather conditions. You cant be too sure.
				
			 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		