Bartimaeus

We’ve been travelling down the Thames for a few days now.  The number of moving boats is significantly smaller than last time we were on this part of the river.  Nevertheless, finding a mooring can be surprisingly difficult.  Long stretches of the bank are lined with massive houses with gardens down to the river.  In many cases its clear the residents don’t make use of the access, but it is often equally clear that they don’t want anyone else to do so.

We have an appointment for later this week, so we have been careful to ensure we had travelled far enough each day.  Once we’ve gone far enough, we try to find a mooring.  I have remembered a few of the possibilities we discovered before, but even then they have sometimes been occupied.

Travelling on the weekend can be alarming.  We found ourselves in the middle of a boat race on Sunday.  Dozens of small boats were suddenly heading our way.  It can be quite worrying when a boat is heading straight towards us with the crew intent on opening or closing their sails.  We’re obliged to give way to them, but that assumes we know which way they are going.  We’d almost cleared the racing course when a rowing four and eight overtook us.  We’re supposed to give way to them too!

We found a mooring in Maidenhead that had been occupied when we’d come through previously.  The centre of Maidenhead didn’t seem very exciting, but we were there on an early Sunday evening, so perhaps it was not at its best.  We found some alarming bat sculptures in honour of Christopher Lee – apparently the Dracula films were made nearby.

Last night’s mooring spot was a pre-booked mooring with electric charging.  On our way down the Thames in July we had hoped to use this mooring, but the electric was out of action. This time we didn’t even have to ask the lock keeper – he recognised our boat name from the advance booking. We went through the lock and then did the alarming looking manoeuvre between the wooden flood guides to moor up next to the electric post.

The space in front of us is reserved for the patrol boat (no sign of it!) and the bank at the back is alarmingly paint scraping concrete.  Fortunately the only ring available for tying the back to also had a small white fender hanging from it.  With some care I managed to get the fender wedged in just the right place to keep the concrete and paint apart.

It took about five hours for the batteries to replenish the charge used since we’d last switched the diesel off.  The charger then switches in to an “absorption” phase where the batteries continue to charge at a steadily declining rate until they can’t take any more (that went on until after 5am).  Fortunately the expertise required to do this is all coded up in the big blue box that sits in the cupboard at the back of the boat.  All I have to do is make sure that the water in the batteries is topped up, as some is driven off by the charging process.

Late in the evening we were interrupted by the carbon monoxide (CO) alarm going off!  We’ve had this happen before when we were plugged in in a marina.  I’ve always presumed it was the smoke from stoves on nearby boats, but I knew it wasn’t that this time.

When we had our boat safety scheme certificate renewed, I had followed the examiners suggestion and bought a separate smoke and CO alarms.  He recommended one that displays the level of CO and sits on a counter.  I was able to take the alarm outside the boat, and to the front of the boat and confirm that the reported levels of CO were lower.  We opened the back door to ventilate that area and the alarm stopped complaining.

This morning I searched for information about CO alarms sounding when charging batteries.  It turns out that hydrogen gas generated during charging can give a false CO alarm.  We presume that this must be finding its way through the back door vent and in to the cabin.  Breathing small amounts of hydrogen is not hazardous, and at the levels reported it is not a fire or explosion risk either!

It is a relief to begin to understand why the alarm goes off.  The next trick will be to work out how to stop the hydrogen finding its way to the alarm.  Perhaps we just need to move the alarm to the other end of the cabin – we’ll try that next time we’re charging the batteries on a still evening.