I took five litres of cream taken with care from milk of the preceding evening. I condensed it in the water-bath to four litres, without skimming it. I took off the skim which was formed above, in order to strain it through a boulting cloth afterwards, and let it cool. After having taken off the skim which had risen while cooling, I put it in half bottles, observing the usual process, and let the water-bath boil for one hour.

At the end of two years this cream was found as fresh as if prepared the same day. I made some good fresh butter with it; making from four to five ounces of butter from half a litre of cream.