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.
In the days of wooden ships with sails, the wind and waves could easily push them against the rocks and wreck them. And so, the need for lighthouses as warning signals arose. One of the Seven Wonders of the Ancient World was a lighthouseâthe famous Pharos of Alexandria, Egypt.It is the first one that is recorded in history and was built about 280 BC. Those records tell us that it was the tallest one ever builtâ450 ft.n the days of wooden ships with sails, the wind and waves could easily push them against the rocks and wreck them. And so, the need for lighthouses as warning signals arose. One of the Seven Wonders of the Ancient World was a lighthouseâthe famous Pharos of Alexandria, Egypt.