The same way you read ANY syringe. From www.wikipedia.com (http://en.wikipedia.org/wiki/Syringes), if you click on the image of the 10ml syringe, you'll see the markings on the barrel.
You measure...
1 ml (millileter) is defined as one cubic centimeter (1 cc) so a 3 ml mark is also a 3 cc mark and hence 1cc is equal to 1/3 of the 3 ml syringe or the 1 ml mark.