Bohaund rock, Isle of Muck

H

Humblebee

Well-Known Member
Joined
10 Nov 2001
Messages
1,843
Location
Home-Granton, boat James Watt Dock, the Clyde.
Visit site
Bohaund rock is apparently in the entrance to Gallanach Bay on the north side of Muck. Martin Lawrence mentions it in the pilot book "Skye and North West Scotland" and the C-MAP chart shows it and gives it a drying height of 3.1m. Now, I was there the other night - neap tides - and have visited the bay twice before, and have never seen a trace of Bohaund. No rock, no signs of a disturbance in the waves indicating its presence, nothing.
Can anyone confirm its existence or is this an anomaly I should mention to the cartographers?
 
Report Via Hydrographic Office

I cant comment on the rock but I have reported anomalies to HM Hdrographic Office many times over the years. There is a form you can use to report anomalies.

HM Hydrographic Office are responsible for the survey data and you can supply information to them from your own observations here. On the right hand side you can down load various forms of which form H102 is the instructions for reporting.

In the past I have sent information in on rocks, depths and magnetic anomalies and most have been incorporated over time. The more information the better. In your case probably your position, time and depth data and a narrative on what you observed.

In short, yes, report it.
 
Humblebee said:
Bohaund rock is apparently in the entrance to Gallanach Bay on the north side of Muck. Martin Lawrence mentions it in the pilot book "Skye and North West Scotland" and the C-MAP chart shows it and gives it a drying height of 3.1m. Now, I was there the other night - neap tides - and have visited the bay twice before, and have never seen a trace of Bohaund. No rock, no signs of a disturbance in the waves indicating its presence, nothing.
Can anyone confirm its existence or is this an anomaly I should mention to the cartographers?
Click to expand...

Thanks for an interesting insight.

FWIW the 1974 CCC Blue Book says Bohaund dries 3ft at LWOS. It goes on to say "at LW the rock shows two heads and the spit is also uncovered, and forms the E side of the bay." which suggests someone at some time has seen it.

I can't see a drying height on CMAP but it certainly indicates that Bohaund dries.

Personally, I'm not convinced that google maps really agree with CMAP & the old CCC. (This opinion based purely on the risky assumption that the dark bits are weed on rock and that the sandy looking bits are not rock.)

http://maps.google.co.uk/?ie=UTF8&ll=56.845569,-6.257529&spn=0.0071,0.022681&t=h&z=16

I guess you'll have to go back at LWS to satisfy your curiosity. I, for one, hope you report back here.
 
Last edited:
Humblebee said:
Bohaund rock is apparently in the entrance to Gallanach Bay on the north side of Muck. Martin Lawrence mentions it in the pilot book "Skye and North West Scotland" and the C-MAP chart shows it and gives it a drying height of 3.1m. Now, I was there the other night - neap tides - and have visited the bay twice before, and have never seen a trace of Bohaund. No rock, no signs of a disturbance in the waves indicating its presence, nothing.
Can anyone confirm its existence or is this an anomaly I should mention to the cartographers?
Click to expand...

Martin Lawrence gives a drying height of 1.2m as does my Imray and Admiralty chart, not sure where Cmap get their 3.1m. info. from but I hope they don't get everything as far out as this, looks like they convert feet to metres at 1 to 1. It is definitely there but often covered. Worth telling them so they can issue a correction though because it is upward it is not a particularly dangerous error.
 
Thanks all

Some interesting replies, thanks all. I had a look at Google Earth and it seems to show the rock much further into the bay that the chart does, and further in than I anchored.
As for the height, I wonder now if I had the electronic chart giving depths in feet, not metres. It was straight out of the box! Normally I use paper charts and it hadn't occurred to me that the default setting might be in feet.
I nany case, the image shown on Google Earth doesn't square with the electronic chart or the pilot book. I'll double check next time I'm there then passon a correction to the cartographers.
Cheers all
 
Humblebee said:
Some interesting replies, thanks all. I had a look at Google Earth and it seems to show the rock much further into the bay that the chart does, and further in than I anchored.
As for the height, I wonder now if I had the electronic chart giving depths in feet, not metres. It was straight out of the box! Normally I use paper charts and it hadn't occurred to me that the default setting might be in feet.
I nany case, the image shown on Google Earth doesn't square with the electronic chart or the pilot book. I'll double check next time I'm there then passon a correction to the cartographers.
Cheers all
Click to expand...

I think they all tally nicely. I did a bit of graphics jiggery pokery to overlay the C-Map chart over the google photo and they match to within a few metres:
 
Last edited:
You must log in or register to reply here.

Share this page

Top