At the bottom of the cooking utensils to pour water and add the plums(previously washed and cleaned from the bones),bring to a boil and cook for 15 minutes stirring occasionally on high heat,then pour a Cup of sugar.not subtracting the fire so as not to interrupt the boiling,when the sugar dissolved pour the next glass,and so glass pour all pounds.Cook the jam on medium heat, frequently skimming and stirring with a wooden spatula 40-45 minutes until tender and the jam has to be beautiful color,plums are evenly distributed in the syrup,spoon should drain fine thread,5 minutes before the end of cooking, add the lemon juice.Hot jam pour into sterile hot jars(I got 2 half liter).roll boiled covers and turning upside down the wrap to cool.Then put away in the pantry.so as not to disturb the "gelation" banks with jam is not recommended to shake.For once not cook more than 1 kg of plums.