"Goody, goody, " said the fairy with excitement, clapping her tiny hands. She reached up and tried to snatch the vial out of Mary's hand. "Gimmie, Gimmie!"
Mary pulled out a large bowl and poured out the contents of the vial into it. The fairy leapt into the sky, hovering over the bowl before diving into it. She began to swallow mouthfuls of the potion, but most of the liquid seemed to be absorbed directly into her small body.
For a short while nothing happened. Mary began to wonder if perhaps each vial could only be used once. Then the fairy's small body began to slowly grow.
The effect was more obvious this time, as the fairy's small body began to double in size. Her tiny outfit snapped off as it struggled to contain the growing flesh beneath it. The fairy didn't seem to mind. She flew out of the bowl, landing on the table and dancing around happily as her growth slowed and gradually stopped. Mary had trouble measuring the merry fairy, hopping with excitement.
"Just as I thought - 4 inches. Each full dose doubles the subject's previous size," said Mary proudly.
"That's great! Can I have another dose?" asked the fairy.