in the summer of 1962, as social change was coming in the u.s., rachel carsons silence ring publish many other events afoot. [inaudible conversations] well -- haflex deriving to wuu38 cell and he create ared 800 of these tiny cells each had two to three million cells in it. each cell in each had the potential to divide another 40 times. if you do the math you realize that simply one little bottle of about ten million cells will produce 22 million pounds of cells or tons rather when it is fully expanded. for practical purposes created a supply of cells that was infinite especially when you realize if you freeze 800 cells an take out one ampuele a decade or 50 years later cells will begin dividing again and they will remember how many times they divide before they were frozen and they'll continue up to roughly 50 divisions to america will use cells today from viles just look this one that they laid down in the srm of 189 -- summer of 1962 excited about the cell and got lab tests that was clear that the cells from mrs. ex-'s fetus were clean and safe, in fact, he sent a young physician back