Yogurt stands in for mayonnaise, and veggies such as celery, onions or bell peppers add a bit of crunch. One serving of egg salad made with two egg whites, 1/2 ounce of plain, fat-free yogurt and 1/4 stalk of celery has 60 calories, less than 1 gram of carbohydrates and 0.5 grams of fat.
The Amazing Inventions of Heron of Alexandria. Heron, also known as Heron of Alexandria, developed many machines and mechanical devices with practical uses, showing that it was possible to take theory and put it into practice. Some of his devices were: 1  A coin operated 'Holy Water Dispenser'. 2  A water organ. 3  The Aeolipile, a steam-powered device.
He made five important assumptions (none of which is perfectly accurate): 1  That the distance between Alexandria and Syene was 5000 stadia, 2  That Alexandria is due north of Syene. 3  That Syene lies on the Tropic of Cancer. 4  That the Earth is a perfect sphere. 5  That light rays emanating from the Sun are parallel.