It was the summer of 1998. Dennis was looking for an off-campus apartment for his sophomore year at Berkeley.

Apartment leads would arrive during the day via e-mail. When I got off work, we would head into Berkeley to check them out.

Pickings were slim. Night after night, we’d drive 100 miles and have nothing to show for it. We joked that maybe he’d have to begin his sophomore year sleeping in a BART station.

Finally we got lucky. We found a clean, affordable one-bedroom two miles from campus, a short walk from Rockridge, Oakland’s village-style shopping neighborhood.

When we signed the lease, euphoria ensued. We skipped up Claremont Avenue, hung a left on College and stopped at the first cafe. Two cappuccinos, please.

This was our top-of-the-world, ain’t-life-good introduction to Royal. Nine years, a bachelor’s degree and nearly a Ph.D. later, we’re still celebrating there. We’ve incorporated this coffee house into the fabric of our father-son relationship.

We meet there anytime I’m going to or from San Francisco. And annually before the Christmas Revels. And always when I’m vaguely in the area. Two caps, please.

Royal, now renamed Cole, is one very cool place. It’s always been wildly popular with affluent hill dwellers, artsy types and academics. In their midst, I feel like a yokel. I carry the taint of having dropped in from the suburbs.

I stand out because I do not wear a vest of yak hair or streak my hair with orange or pierce every conceivable patch of cartilage or feed muffin crumbs to my golden Ethiopian whippet.

No, I just sit there, unadorned, and sip my cappuccino with Dennis, while observing the members of the Rats motorcycle club at their gathering spot across the street.

Royal, now Cole, is where I get caught up on Dennis’ life. He doesn’t share much in e-mails and extracting anything insightful over the phone is like interviewing Al-Qaeda at Guantanamo.

But ply Dennis with a cappuccino and wait a while and maybe I’ll find out what’s going on.

I’ve heard plenty of humorous anecdotes about the math classes that are part of his teaching duties as a grad student. It seems that students are students. Whether at Napa High or Berkeley, the games they play with teachers are the same.

It was two year’s ago over cappuccinos that Dennis hailed a woman exiting the produce store across the street and invited her to join us. This was the first I’d ever heard of Margaret, now the significant other in his life. But for Cole’s, might she still be a mystery?

Although Dennis’ academic life is all about math, we’re never been able to talk about the essence of it. Cappuccinos are a powerful elixir, but they cannot  make math matters comprehensive to the likes of me. I have the math innocence of a new-born.

So we talk around this thing that cannot be discussed directly lest it befog my brain. It is enough for a father to know that the math is progressing, the thesis taking shape. I will drink to that.

Ruefully aware that his days at Berkeley are counting down, I took a vacation day Thursday to go in and spend time with Dennis. We BARTed into San Francisco for a few hours at SFMOMA. The art was pleasurable enough, but it wasn’t the day’s anticipated highlight. That would be the caps that followed at Cole Coffee.

Ordering the usual, we found a rare inside table bathed in the mellow sounds of Sinatra. In short order I got the news. His Ph.D. nearly in hand, applications for post-doctoral research positions are going out. He could be gone early in the new year. Out of state is almost a given.

That feeling in my gut? Separation pangs. Not quite as bad as watching your child depart for his first day of kindergarten, but definitely similar.

Great news, Den. How exciting. This is the milestone you’ve worked so hard for.

Looking around, I felt a shiver. Is this it? Are we at Cole’s for one of our very last times?

I would not freeze time, certainly not, but if I could I might slow it down. Would it hurt anything if the next few months lasted twice as long? Long enough for a dozen more cappuccinos.