T he commemoration of the first world war has combined with the floods to make this the year of the sandbag. On television, sandbags are inescapable. There they are in flickering black and white, lining the tops of Flanders trenches; there they are again, in colour this time, freshly plonked against doorsteps in Somerset and garden gates in Berkshire, and sometimes laid by troops in long lines in the hope that water can be held back or steered politely towards a different part of the home counties.

Like the building brick, the roof slate and the railway gauge, the sandbag has a standard size common to most of the world – a good example of the Darwinian process that in technology weeds out the nonconformist. Usually they measure 14in x 26in, light enough when filled to be easily carried and slung about by troops who might urgently need to build a parapet or a parados (the first in front of the trench, the second behind it), or to erect a protective wall where the ground is too hard for a trench. Sandbags stop shrapnel and bullets – 15in was the furthest a first world war bullet would penetrate a sandbag wall – and their granular composition is particularly useful in absorbing blasts of high explosive. That same composition makes the sandbag less effective against water, which will eventually seep through and sometimes leave dangerous sewage deposits in the sand, but nothing, so far, has rivalled its cheapness, robustness and portability as a method of flood control. An empty sandbag can travel thousands of miles as flat as an ironed handkerchief, to be swollen with the weight of earth, the cheapest and most widely available of materials, only when it's next to where it's needed.

Most bags are now made from woven polypropylene, an invention of German and Italian chemists in the 1950s, but the originals were of hessian or jute, and known in India as gunny bags, a description descended from an old Sanskrit word for fibre. Jute is an Indian plant, but Dundee monopolised its manufacture as a textile, importing raw jute and exporting finished goods, until Scottish capitalists woke up to the fact that it was cheaper to make jute fabric closer to the source of the raw material, where labour costs were far lower, and began to build factories in Bengal. Calcutta replaced Dundee as Juteopolis in the Edwardian era, and sacks from its looms filled the world's warehouses as the containers of Australian wheat and wool, Java coffee, Cuban sugar, North American potatoes and South American nitrate. This was the gunny bag's heyday – world trade depended on it – but the phenomenon that set the seal on its success was the dug-in frontline, which by 1915 ran from the Channel to Switzerland.

I visited a jute factory in last week's column, and I apologise for returning to the subject. But the story is interesting. Indian factories sent about 1.3bn sandbags to the Allied armies, mainly for use on the western front, almost doubling the value of India's jute exports between 1914 and 1919. The profits of India's jute industry, expressed as a proportion of paid-up capital, ran at 10% in 1914 and 49% in 1917. In 1916, the year of the Somme offensive, they touched 75%. After the war, the British owners of the mills spent their dividends on town houses, steam yachts and etchings (the last an asset bubble that burst, never to recover, in the 1930s). But the higher prices that jute had commanded during the war had a more fundamental effect in Bengal's jute-growing districts, where almost every jute farmer decided to rebuild his house with a corrugated iron roof. Unlike thatch or tiles, corrugated iron made a household proof against the monsoon rain, and in the early 1920s phenomenal amounts of the galvanized sheeting were shipped up-country. The typical Bengali house changed not only in the way it looked, but also in how it sounded, when during the wet season its roof now echoed to the clatter of rainfall bouncing off a hard metal surface.

Not for the last time, though here in an indirect way, the sandbag helped keep people dry. How many lives it has saved is impossible to know, but perhaps a great many: from maiming and death by machine-gun fire and shrapnel, from the mania and terror induced by artillery shelling. All this, plus innumerable fitted carpets saved from drowning. A world that recognised the contribution of inanimate objects to our welfare, even one as lumpen as the sandbag, would surely award it a medal.

In the Guardian's travel section last week, I came across an entire page devoted to the Glasgow district of Finnieston, which according to the writer was "coming alive with pop-up bars and eclectic restaurants, plus myriad artistic outlets and events". The list included a place that sold razor clams and was "both brilliantly Glasgow and brilliantly Finnieston"; a hairdresser's that provided rum and mango cocktails; and a boutique where an Italian designer had given the Glasgow hoodie "a revamp with elegance and a touch of tartan". Of course, many western cities have reinvented or at least relabelled quarters that might otherwise have died of post-industrial depression; had the piece described a vibrant or edgy part of Barcelona, Berlin or Bristol I wouldn't have noticed. But Finnieston …

I lived there at the end of the 1960s in a sandstone tenement that 100 years of smoke had turned black. A more particular description invites disbelief: the close reeked of cooked meat from an adjacent butcher's and had gas lamps that were lit every night by an itinerant lamplighter; the back court faced a lemonade bottling factory owned by Robinson's; bottles rattled throughout the day, while at night, just below our windows, a flickering electric sign read "Robinson's – makes thirst a joy!" I lodged with a married couple who were also my friends – stern aesthetes who bought second-hand cane furniture and cooked Italian food and told me I should always wear black socks, but who were not in any sense incomers and gentrifiers. Their parents lived close by, up other grubby closes, and had ordinary jobs – as a barber, as a sailor with the Clyde Port Authority. The sailor and his wife came from Stornoway – Finnieston in those days had a settled Hebridean population, but otherwise it would be hard to call it a community, which according to the Guardian report is what you get a real sense of these days. The cinema had closed and the docks were emptying. Men of a certain age went to the Ben Nevis or The Grove bar and lounge; women tended not to. Once, a young couple from London came to visit and enthused about tenement life and how it could be transformed if the closes had lockable doors to the street and the common stairs were carpeted. It was funny – we laughed about it for weeks, not having the foresight to see that razor clams and mango cocktails, never mind stair carpets, would one day be part and parcel of Finnieston life.

Writing has always been the hardest thing to film, or at least to film honestly. So little happens: pause, frown, pause, sigh, type a little, delete, type a little differently, stop. As for editing a literary periodical, how much visual boredom can a film take? Nevertheless, Martin Scorsese's next film, which previewed this week as a work in progress at the Berlinale, will be a documentary on the New York Review of Books. Scorsese has been a fan of the paper since it began in 1963, and his film centres around the lively 83-year-old figure of Bob Silvers, its editor since that date. A cinematic parallel is hard to find. "Hitchcock shoots Encyclopaedia Britannica story" is missing from the archive.