Creamed Peas and Cucumber

4 cups shelled green peas
1 medium onion, sliced
1 teaspoon salt
2 cups boiling water
4 small cucumbers, peeled and diced
3 tablespoons butter or margarine
1 cup cream or rich milk, scalded
1/2 teaspoon vetsin

Combine the peas, onion and salt in saucepan. Add the boiling water and cover. Cook until peas are almost tender, (about 15 minutes). Add the cucumbers and continue cooking until these are also tender. Drain, cream and let boil once. Add vetsin. Serve very hot.