Gordon Gribble is a professor of chemistry at Dartmouth College, where he has been on the faculty for 40 years. He lives in Norwich, Vt., and Lebanon, N.H., with his wife Louise. The following is an edited interview.

I’m a synthetic chemist. I build things. I make molecules, anti- cancer drugs and so forth, so I’m always building stuff. I had Lincoln Logs and Erector Sets when I was a kid. In fact, I had a great set of Lincoln Logs my mom tossed out when I went to college. This is a substitute for those.

I start out building the four corners and I try to cant them in to the center so when the frost heaves come, which always happens, it doesn’t collapse. When the snow builds up, the roof will sag a bit, but it holds.

I like to have it really neat and smooth. Stacking it’s almost an art form: big ones down at the bottom, bark side up if you can, and the corners have to be good. I’ve never had one fall over.

I had a colleague help me build one one year, and his part fell over in a week or so. He was fast, just pile it up basically, and it just collapsed. I never told him, I just built it back up myself.

I’ve made maybe 4 or 5 of these over the years. I used to put them out in the field by the neighbors’ house but then they’d get the credit. And they got tired of answering the door with people saying how much they liked it, so now I have it closer to the house.

Once you have it up and have it looking the way you want it, it’s a shame to burn it, so I try to leave it up as long as I can. When the time comes, I think I’ll start from the back to keep the facade as long as possible.

When it was all finished and it looked nice and pristine, I used to put this sign up, in big black letters, “Now Renting.” One day, some homeless guy stopped to ask how much I would charge. I don’t know if he was pulling my leg or not, but I don’t put that sign up anymore.