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A Change in the (h)Air: Bow Making and Climate Change

Andrew Bellis in his workshop

Andrew Bellis.

For openers, I have to state that I’m writing this from the south coast of the UK. The weather/climate will doubtless be different where you are, but it may well be that changes in it are occurring there too.

More Than Quirky British Weather

I am not sure when I noticed the bows and instruments in my workshop being affected adversely by the weather. (Our changeable weather is a constant conversation opener for the British.) It was certainly not the 1980s or the early 1990s. But, by the 2000s, I needed to be much more aware of my environment and materials.

In the media, this was referred to as “climate change.” A hygrometer in my workshop measured the water content in the air. It could go from 15% to 40% (or the other way) in one morning. Just these last two days (early August 2022), it has risen to 55% and then dropped to 15%. Remember that in the museum world, anything less than 20% is regarded as desiccation.

Climate change. We’re bombarded by all sorts of worrying information. Whatever the causes, we have to live with it. Having started making bows in 1978, and performing as well, I’ve had time to note the more significant changes, so here’s a run-down.

William Charles Retford, (c.1902).

William Charles Retford, (c.1902).

It’s not only climate change that affects our instruments. As William Retford wrote in the 1950s in his excellent Bows and Bow Makers

“In recent times war, and rumors of war, combined with the antics of politicians, have made trade difficult.”

He could have written that yesterday.


horse hair

When I started making and restoring seriously (1980) and needed to buy hair in bulk (“tails”) rather than in individual hanks, my mentor recommended Arnold & Gould in Suffolk, particularly their Italian hair. All well and good, but just a year later, it was unavailable. This was due, they said, to “market forces” – or, quite possibly, the Italians not considering it worth their while. Arnold & Gould stopped trading in the 1990s; their mill is now a housing development.

As a replacement, I used Canadian hair, a little thicker, but well-received by players.

Then that became expensive, and the Chinese saw an opportunity to get into the market and now seem to supply all the hair, no matter which country actually supplies it to the bow makers. It is thicker again, sometimes uselessly weak, sometimes perfectly good, but that’s not new. Hair always needed “dressing” before sale.

Chinese horses

Chinese horses. Photo by Gigi on Unsplash

We find a reliable supplier and stay with them, hoping their buyers and “pickers,” those who sort through the hair for the bow maker’s requirements, are up to the job. One supplier – always claiming to be a specialist in the trade – received and sold a quantity of “stretchy” hair, particularly useless in strong cello bows, but surprisingly not spotted until quite a few tails had been sold; I could never trust them again.

Hair has become thicker due to the type of horses it has been gathered from (and their diet/living conditions), so good playing hair is scarce. To cope with this, make a rehair last – there are tips on my website.

In the past, bows played for years, if not decades. The “once every six months” rehair was unthinkable and unaffordable; it has never been a cheap job. To summarize: use far less rosin (hair retains it excellently – clean your strings instead) and keep your hands clean before playing. And don’t think that being a hair-breaking showperson makes your sound any better…


Endangered Species

Our lovely bow-making wood, Pernambuco (Paubrasilia echinata) is now a protected species under international law. In Brazil – the only place it grows – it is illegal to fell such a tree. Even if it is your own property, felled on your land, it is illegal for any tree to cross customs lines. This is not necessarily a climate change response, but more a political, economic, and legal one.

Pernambuco tree.

Pernambuco tree, Botanical Garden, São Paulo. Photo by Mauroguanandi. Public domain. Source: Wikipedia.

However, it seems the laws have not stopped people from using it, claiming their raw timber is “old” – bizarre stories about fence posts and railway ties abound. Those who own the land on which the pernambuco is situated are also not deterred from logging what they perceive to be “their” trees.

The current “environmental concern” of organizations such as the IPCI to replant pernambuco are ridiculously naive. Though they seem to think it’s twenty years before a tree can be mature enough to be cut for bows, in reality, the trees take ten decades or more to mature. I can’t wait that long.

Process of Darkening a Bow Stick

Pernambuco wood

Paubrasilia. (1 October 2022). Photo by Fopseh. CC BY-SA 4.0. Source: Wikipedia.

Once upon a time, if the maker wanted to darken the bow stick, it was necessary to resort to chemical means, using nitric acid and/or ammonia. Nowadays, if using an oil finish, a few days in the sunshine will provide similar results for free, and it will go on darkening too; the summer sunlight is somehow more fierce than a decade ago.


Rough Ebony

Rough ebony. Photo by OboeCrack. CC BY-SA 4.0. Source: Wikipedia.

This heavy hardwood is, surprisingly, one of the most reactive woods to moisture change that I know. For many, it was a mystery why cello fingerboards would suddenly take to detaching themselves in the Spring season, and previously well-behaved pegs would slip overnight.

A bow nut (“frog”) made by me with perfectly level silver/pearl/ebony parts would no longer be so by the time I saw it a couple of years later. The metalwork would have become “proud” of the ebony, the wood having shrunk.

The fingerboard problem (not limited to cellos) was due to the ebony wanting to change width, but the glue doesn’t allow it until the altering wood overcomes the glue. It is not the maple of the neck changing size.

Planks of Gabon ebony (in front)

Planks of Gabon ebony (in front). Photo by Disputantum. Public domain. (22 September 2022). Source: Wikipedia.

For both ebony and pernambuco, their environments were subject to coastal storms. The island of Mauritius produced the best ebony (dense in both weight and color), and enough trees were brought down by storms to supply our needs. That was their perfectly satisfactory method of controlling the tree population! Of course, the moneymen saw an end to that. In an entirely similar scenario, enough ivory was sourced from naturally dead elephants to supply bow makers over decades.

Working Environment


Hygrometer. Photo by Kaffeebart on Unsplash

As I write (August 2022), the UK is experiencing a longer than usual period of a complete lack of rainfall, predicted to last two months. At the same time, the atmosphere varies greatly in humidity.

When the moisture in the air is high (60%), I have to hair bows “long” because when the player wakes up the next day with the humidity returned to a more normal 30-40% (indoors), they don’t want their bow hair too short and already under tension even when “relaxed.” Hair is surprisingly hygroscopic.

Wood and other materials and sundries need to be protected from extremes, especially glues and varnishes, which would otherwise spoil prematurely. Through the summer, I have to adopt the European lifestyle of the midday shutdown (“siesta”), because it’s simply too uncomfortable to work.

Air Conditioning (AC)

Prevalent now in concert halls throughout the UK, air conditioning is the enemy of our musical instruments. Without humidity controls, the system can dry the air beyond the normal environmental levels, around 25%. Basically, the woods are being subjected to artificial desiccation (and you are, too!).

Even worse, at the end of a rehearsal, the cello will be taken back to the outside environment for a couple of hours, only to be subjected to the AC for another three hours before returning home again.

It’s a wonder they play at all, let alone with the finesse expected of a top-quality product. When my wife and I traveled to Cremona a decade ago, it was obvious why violin making settled there – although unusually warm for September (so we were told), the atmosphere just felt “right.” I wished I’d taken my Cremonese-made viola (1976) just to see how it responded. Compared with that microclimate, the UK is (generally) damp and cold.


A luthier friend of mine made a good living in his retirement by producing copies of eminent chamber musicians’ instruments for them to travel with abroad. The players simply did not want to take the risk of taking their precious original instruments onto airplanes and then into foreign climates beyond their control.

The maker had the bonus of being able to intimately measure the old instruments! He never attempted to copy age in the wood or varnish, so they always looked “new.” Much to the player’s consternation, not once were the instruments’ origins ever questioned. Audiences assumed such prestigious players would surely only ever own fine old instruments…

If you move permanently from one area to another, either a significant distance and/or to a different microclimate, give your instrument time to acclimatize and be prepared for previous repairs to come apart. “Cello glue” does become brittle with age, but this means centuries, not decades. However, a change of climate might just trigger a seam to open.


For violins and violas, modern synthetic core strings overwound with metal are just about the best at producing good tone and coping with the conditions described above. For cellos and basses, metal-cored overwound strings seem to be the preferred choice.

For those of you using uncovered gut strings – good luck! Keep them oiled (apart from the bowed area, of course) and, where possible, out of UV; if allowed to dry out, they will become irreversibly useless.

What can players do to help?

Washing your hands before you play will make bow hair and fingers last much longer. Eating a packet of crisps (potato chips) before playing, without cleaning your hands, can ruin both rehair and strings.

I think it is worth repeating: there is absolutely nothing individuals can do about climate change. Single personal alterations to behavior will not have any effect. Targeted protest might, but you’ll need to be brave to take on (for example) the aviation industry.

What we should do is adapt to cope as best we can. When social chamber music started, with home-based viol consorts, there was no heating other than wood fires, no lighting other than beeswax candles, yet many of the instruments survive to this day. Strings would have been precious, and rosin simply the sticky lumps obtained from drysalters. Makers of instruments would have found their specialist materials difficult to source, explaining the high cost (and therefore exclusivity) of their products.

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