What I ended up using for the most part was a lot of 'rule of thumb' measurements about changes in material properties at temperature, and a lot of gu...ssing. Modern civilization is based on accurate measurement. I'd known this in making sure I had good calipers and other physical measurement, but I'd forgotten about temperature. The answer was is my books, of course but I couldn't find it.We used the clearest glass we could produce to create a better roof and walls for the greenhouse. The best. "You ever fuck her like this? You know, so fuuuucking smashed? I bet you have. After watching her walk around in that sexy little skirt. Bet you get a real boner, but then she's too plastered so you fuck her anyway. Oh she makes us want to cum!"Will and James, now frantically masturbating either side of her, were ready to blow. Ryan filmed and all that could be seen on the screen was the base of her buttocks getting fucked and the two cocks being rubbed furiously, banging down on the skirt. But her small throat will never be able to take it all, at least not without some help. So I tell her " let me help you". And I get up and pull her to the edge of the bed. Her head hangs down from the edge and place my cock head against her lips. Her mouth opens willingly and I slide it in. I keep it shallow at first, slowly pumping my hips. She puts a hand on her crotch and plays with herself. Then with the saliva flowing I squeeze her neck tightly with my hand to distract but also warn her of. Do you think it would help if I masturbated as well?"Andrew grinned, "Yeah, I think that'll help a lot."Cynthia was already sitting on the couch facing Andrew with her legs crossed. She slid her butt forward until her head rested on the armrest and then hooked her right leg over the back of the couch. She placed her left leg over Andrew’s right knee. She adjusted her position until she felt comfortable. Her skirt still covered her white panties. She kept her eyes on Andrew as he hungrily.