What was the S.R.D. jar?

There are a lot of stories about the meaning of S.R.D. 
The most possible meaning of S.R.D. is Service Ration Depot some say it is:Supply Reserve Depot.There is still doubt about it.
That is so because the same letters where also found on other suplies as soda and food. A collector told me he has even a wooden box of chocolat with S.R.D. on it!

other hypothetic meanings are:

Services Rum Diluted
Service Reserve Depot
Special Red Demerara
Standard Rum; Diluted  
Service Rum Distribution
Service Ration Department
Service Rum Department

Soldiers slang for S.R.D.:

"Seldom or Rarely Delivered
"Soldiers Run Dry"
"Soon Runs Dry"
"Seldom Reaches Destination"


The rum ration was introduced in the winter of 1914, as a remedy for the consequences of the bad weather conditions and cold.
Strange is that alcohol is not a good remedie against cold...
The S.R.D. JAR for rum is 1 (UK) gallon (4,546 litres). One jar for 64 men.
In 1918 1/3 pint (0.16 litre) appears to have been the average consumption per soldier per week. Some books say: 1 spoon each. Some people say this made soldiers willing to fight. That is almost impossible, drunk soldiers were heavely punished by the commonwealth, even behind the front. So why should they make the frontline soldiers drunk then?

Having been utilized by the tens of thousands, these jugs littered the western front during the post war years.
They still turn up at flea markets and junk shops in North-west France and Belgium. It is also a typical WW1 relic in the Salient.