Barnaby Joyce thinks that because carbon dioxide is colourless and odourless, a steadily increasing concentration of it in our atmosphere is harmless (''Where will guilt by conversation strike next?'', October 4, p15).
A substance's colour or odour has no bearing on its potential to harm humans or nature. Carbon monoxide, for example, is colourless and odourless, but it also can be very deadly.
Several of the chemical warfare nerve gasses, such as sarin, are colourless, odourless and tasteless.
I'm surprised Joyce has managed to navigate his 45 odd years safely, if his method of determining the danger of something is simply to sniff it.
C. Gunn, O'Connor
Sickening smoke
The government set new diesel-emission standards to protect our health. Despite the extra costs on new vehicles, four-wheel-drives must emit no more than 0.005 grams of particulate pollution per kilometre travelled.
CSIRO's research shows new wood heaters emit about 10g of particles per kilogram of firewood.
With annual average fuel consumption of 3.7 tonnes a year in Canberra, the average new ACT wood heater will emit 37kg of particles a year - 370 times worse than a new diesel engine.
Research shows there is no safe level of particulate pollution.
New Zealand set new wood heater standards; its industry soon developed new, cleaner models.
The real madness would be to risk our health by continuing to install wood heaters that are 370 times dirtier than the average new diesel 4WD, instead of waiting until new, clean-burning models are developed that won't make people sick.
Dr Dorothy L. Robinson,
Australian Air Quality Group
A dead issue?
As the ACT election campaign rolls on with new promises every day from all contestants, I have looked out for some reference to funding of a new cemetery in south Canberra, especially in the Brindabella electorate.
With the leader of the Canberra Liberals, Zed Seselja, now a contestant for one of the Brindabella seats, I was half expecting that the proposal to build the new facility opposite the Mugga Lane tip might be revived.
The public reaction to that proposed site a year or so ago was unfavourable. Does this mean it's now a dead issue?
E. L. Fisher, Kambah
Children need rights
Clearly, the four Queensland girls forcibly deported to their father in Italy, and other children involved in custody battles, lack any human rights in Australia (''Judge orders four sisters be returned to Italy'', October 4, p4).
The girls, aged nine to 15, are old enough to decide which parent they would like to live with. Yet the Family Court has treated them as commodities, understandable only if they were infants under five.
It's time to change the Family Law Act and the Hague Convention to give the children of custody battles the right to determine their future.
Much has been written recently in The Canberra Times about giving prisoners human rights; let's give the children in Australia some rights, too.
Vicki Lilley, Monash
Bright Mr Chips
The Australian Catholic University's vice-chancellor says ''we want Mr Chips, not the nerds from The Big Bang Theory'' (''Plan to lift teacher quality fails grade'', October 4, p6).
It's worth noting that the Mr Chips character was apparently based by its creator on W. H. Balgarnie, whose academic achievements included a first-class honours degree in classics from Trinity College, Cambridge.
Whatever his other attributes, he would therefore also have been one of those teachers, perhaps more common in the past, of good intellect with an academic grounding of substance in the subjects which they teach.
I suspect his ATAR score would have been quite impressive.
Robin Oldham, Rosedale, NSW,
Wealthy pensioners
Could someone explain how extending the retirement ages of judges and military personnel will reduce demand on the Commonwealth's age pension system (''Call to clear hurdles to a longer working life'', October 3, p1)?
Given the level of remuneration, including privileged standards of taxpayer-funded superannuation, already enjoyed by employees, compared with mere mortals in the private sector, I would have thought most would neither need the age pension nor be eligible for it. The suggestion that keeping such people employed would create savings for the public purse and contribute more tax revenue is a nonsense, given that these folk are paid from the public purse.
The problem with people like Age Discrimination Commissioner Susan Ryan is that they've never had to survive in the real world and therefore don't understand that many older people would like to keep working but can't find work, as their contribution is often simply not valued or wanted.
Rather than coming up with silly, half-baked ideas to extend privileges for those who already have them, Ryan would do better to come up with innovative policies that create real diversity in the workplace, including employment of people of all ages.
John Richardson, Wallagoot, NSW
Pondering pickles
Robert Willson (Letters, October 4) reckons venerating the pickled hand of St Francis Xavier is no more credulous than seeing the pickled heart of Phar Lap. Surely the credulity lies in the metaphysical baggage one brings to these objects.
Let's assume they are original body parts and that a theoretical punter is beguiled by both.
Given Phar Lap's want of Catholic zeal, our punter would hardly suggest that the horse's body is incorruptible, even though it was stuffed and preserved; yet, although St Francis Xavier never ran successfully in the Cox Plate as a five-year-old old carrying nine pounds, one can imagine the punter murmuring to the saint's desiccated 16th-century hand as if it could affect outcomes at Moonee Valley.
Peter Robinson, Ainslie
