There's always a sense of expectancy when you are camped in front of a glacier awaiting the inevitable thunder of ice breaking away and crashing into the sea.
But glaciers don't work to your timetable: you can wait in vain.
Today is another of those days as we sit in our cruise ship a kilometre or so away from PIO X glacier in the Chilean fjords awaiting the "calving" of a new iceberg.
Captain David Box swings our ship, Adonia, in a slow sweep. We watch - and listen - from our cabin balcony.
As we scan the glacier, hoping for some action, we follow some dolphins playing in the calm water around us.
PIO X glacier, 64km long, up to 6km wide and 80 metres high, is the biggest glacier in South America, as big as Chile's capital Santiago.
We've have sailed up the Chilean fjords, along the Beagle channel from Cape Horn in the south, into "glacier alley", beneath the towering grey and barren mountains in one of the most remote, lonely, wild-but-beautiful parts of the world. It is known as the Ring of Fire, a loop of glacier-clad volcanoes.
With almost 2000km of scattered islands, fjords, snow- and glacier-capped mountains, lakes, forests and thermal springs, the Chilean fjords between Patagonia's Puerto Montt and Punta Arenas, are comparable in size to the fjord coastline of Norway.
We steamed past the Amalia glacier, but it was obscured by the misty rain.
Typically, bad weather can be part of the region's personality. Dense fog and showers can quickly give way to brilliant sun. Grey cliffs and ice can emerge suddenly from the fog into sunlight, only to disappear again under the next bank of clouds.
Ribbons of snowmelt wind down the mountains into the sea. The Andean mountains are a distant backdrop as they curve eastward and finally sink into the sea.
The greens of the vegetation stand out against the grey rocks. Around us is icy blue water. And between the mountains, the bluish-white glaciers are flecked with grey volcanic dirt. They flow in shining rivers of ice down the valleys toward the glacier faces and the sea.
Apart from a distant, small fishing boat cutting a small bow wave on the flat sea, we feel alone, like explorers seeking adventure.
Earlier we had spotted a magnificent Andean condor circling above. And a killer whale, the orca, passed on its way to who-knows-where.
Despite the apparent emptiness, the Chilean fjordland is a busy highway for cruise ships and ferries.
Today we are fortunate to be the only ship - apart from the fishing boat and a passenger ferry - in sight.
To get here, in the waters off Chile's Bernardo O'Higgins National Park, we have negotiated a baffling maze channels and fjords that only our Chilean pilots could possibly navigate.
Because of its remoteness and terrain, Patagonia can be difficult to get around. The only real road is the southern highway, around 1200km of bumpy gravel road. It stretches from Puerto Montt south to Villa O'Higgins. So the best way to see this magnificent landscape is, therefore, from the sea.
If you are not on a cruise ship, one of the best options is the multifunctional Navimag Ferries, which run a four-day trip from Puerto Montt in the north to Puerto Natales in the south, the gateway to Torres del Paine National Park. Carrying 30,000 passengers annually, it is at once a floating hostel, cargo carrier and transport lifeline for local inhabitants. About half the space on Navimag's ferries is reserved for cargo.
Travellers share decks with vegetables from the central valley and meats - maybe even live cattle - from Patagonia. Cabins are tight but comfortable. Groups of young backpackers gather on the top-deck pub, while families and older couples play card games over bottles of Chilean wine.
Others admire passing scenery from the large open decks, or take shelter from the wind in the ship's bridge with the captain and crew. All this is part of the "Navimag Experience".