Had opened a gallery I already had strong connections with New York, because I was taking work on consignment from New York dealers. So I already knew a great many of the dealers and the artists here. It wasn't cold for me.

I remember when I went to a gallery in Paris at one point, they had drawings of earthworks set in different places. I asked the person sitting at the gallery desk where these works were - where in France they could be found. She looked at me in horror as if I'd asked something completely insane. She said, "Well, of course, these works don't actually exist. They're concepts."

What's happening in the larger world always influences art. When I first started the gallery in 1959, one of the first things I learned was that most people assume artists know one thing and one thing only - that they were idiot savants. I found very quickly that most artists were very informed and very aware of what was happening in the world around them. So all of those things go together, especially for earthworks. And at that time there was such an intense interest in American art. So there was a great deal of attention paid to where it was going.

I think that Walter De Maria's Lightning Field, Michael Heizer's City, and Charles Ross's work in Star Axis New Mexico , all three will last for a millennium.

There's a definite connection in terms of objects at hand - dealing with objects or material at hand. Pop art was very much enamored with popular imagery, and popular imagery was of course available and at hand. And land art was also using what was at hand.

I myself had lived in the San Fernando Valley many years ago, when it was a much wilder place, and we used to go walking in the wild areas. So that early experience had a lot of similarities for me to the places that Double Negative was being done.

I think the four land artists I showed all worked within a few years of each other. And they were standard bearers, I suppose, for land art. They each did very separate things. Apparently, later in California, a lot of artists started working in that medium and there was something of a rush of earthworks. But I wasn't involved with that.