That means, among other things, that no mass can change its velocity in zero time. Am I right so far?’ ‘Yes, keep going.’ ‘Well, when an objec... is first moved, from a standstill, there has to be one instant where the mass has gone from not moving to moving in essentially zero time. Wouldn’t that require an infinite force at that instant?’ ‘You won’t like my answer doc. I’m not copping out. Acceleration is the change in velocity with respect to time. In the absolute instant an object starts to. She reached out and put one hand behind my neck, and pulled me close to kiss. I could feel her tongue starting to probe my mouth, and I started to probe hers. She pushed her ample boobs into my chest and I could feel my cock straining to be set free. I bent down and took one of her nipples in my mouth, feeling it stiffening with every kiss and lick, as I played with the other in my fingers. Her moans of pleasure were some of the sweetest things I’d ever heard, she took my hand and moved it down. .the vibration was so strong. I had had a virbator in my ass before,but this was like a jet engine compared to anything I had used. She handed me the lube and old me to rub some on my cock and some between her tits. I massaged her tits and spread the lube all over them. The I squeezed them together and slipped my cock in between and slowly pumped my cock in and out as I squeezed them together. I was in heaven. She was very gentle and slowly fucked my ass, allowing me to feel the vibration. We passed through the gates to the place where we had laid down before; now in broad day it seemed dangerously near the lane. There was a sinking in the surface a little further on where cows had trodden the ground down to get to a ditch; there she put down her dinner-basket. Throwing up her petticoats, I saw her cunt was dark-haired. We fucked rapidly, no fumbling, stink-fingering, or frigging. I gave her ten shillings. "Give it me in silver", said she, "if I change it in the village it will.