Thomas Romney Robinson to Faraday   16 November 1863

Observatory | Nov 16. 63

My Dear Faraday

On receiving yours of the 3d¹ I wrote to the members of my Committee, to ascertain what they thought on the question of applying to the Council of the British Association for permission to append to our Report your letter to the Trinity Board. I also consulted a friend of ours, of commanding influence in that Council. The last answer came to me only on Saturday² - their opinion is that it should not be so published³; they assure me that none of them gave any authority to the Athenaeum⁴ to use the language which it employed; and suggest that it rests with you to disclaim in that journal the sentiments which it attributes to you.

As to the language of the Report itself (of which I sent you a copy) you have said nothing. If it gives you pain I am ready to modify it, as far as I can without failing in my Duty. Would you prefer something of this sort. After the words “we recommended to the Board of Trade” to substitute [These opinions he seems to have formed; not from any doubt of the importance of the subject, to which he bears the fullest testimony; nor from any conviction that the proposed experiments are useless or impracticable, for he does not discuss them at all; but from a dread of the difficulty, the magnitude and the expense of the Investigation. These we think he exaggerates; but even taking them at his estimate, we do not think they will be accepted by the Public &c]⁵[.]

I am a little surprised at you asking me to shew you in the Memorial⁶, the Proposition of which in my former letter I gave you a summary: this makes me think you have not a copy of that memorial, and I transcribe the part in question; premising that in the earlier part we had assumed (on grounds which I think sailors would fully accept) as the criterion of an effective signal “that it must be distinctly audible for at least four miles under every circumstance. It runs thus

“If, as we hope, you feel sufficient interest in the matters above mentioned to direct such an investigation of them as may lead to practical results we would further take the liberty of suggesting what seems to us likely to be the most effective and economical way of carrying it out: at the same time offering what ever further information we may be able to afford.

The experiments might centre in the Flagship at Spithead: one of its officers could probably be found who would take an interest in the research, or a supernumerary might be appointed for this special object. He should be charged with the general control and in particular with making the signals. These should be observed from various points at Portsmouth and on the Isle of Wight, so disposed as to give distance from two to ten miles if possible, and so distributed that some may have the signals up others down the wind, which is an essential condition. Portland seems also to be very suitable, and perhaps Weymouth Coast Guards or other officials can probably be found at any of these stations to observe the signals; but in any case it is necessary that the persons engaged in the experiments should be habitually on the spot so as to profit by the occurrence of a Fog without any delay.

The process would be of this sort. When the Fog seems to the Directing Officer sufficiently thick, he sends word to the different observers of the Time and Nature of the intended signals. He and they then measure the fog by the means already suggested, or some equivalent. The signals if fully carried out should be

1 Guns

2 Bells Gongs Drums

3 Steam Whistle blown by steam from a small Boiler, and by air condensed to the same, unless it be found that both are equally audible. The pressures should be carefully recorded.

4 Two or more organ pipes, one whose Pitch can be varied at pleasure, one with a Reed; connected so that they can be sounded together or separately.

5 Holmes’ trumpet, Dabolls, any other which appears to deserve a trial

6 A Siren of about 8 inches diameter, supplied with water by a hand pump under a head of about 30 feet (which must be recorded); by increasing the head the pitch rises

7 An organ pipe of variable length, to be sounded under water as the Siren

Each observer when he hears these signals should note the time, and his impression of their distinctness. He should also try how near he can estimate their Direction. For this purpose, unless he can thoroughly depend on his freedom from Bias, he should be blindfolded and turned about till he loses his bearings. He should also try, as already suggested, the aid of Acoustic tubes. A speaking trumpet will in the first instance be the most convenient. The Direction and Velocity of the Wind should be recorded. The returns from each station should be sent without delay or comparison to the Directing Officer[.]

The chief points to be attended to in these trials are

1 The relative efficiency of Guns of various calibre and with different charges of powder

2 Weight of Bells and Force of Blows measured by the weight and fall of the Hammers

3 In the Wind instruments, the effect of varying the pressure: it is probable that each will have some appropriate force of blast which will give a maximum result

4 The two organ pipes are first to be sounded successively on the same note to ascertain if the Reed have any advantage; then the Variable one is to be gradually sharpened through a considerable range to find what pitch is best for distance; and lastly both beginning in unison, one is sharpened to examine the effect of Concord and discord through a large portion of the Scale. They should also be sounded continuously, and with short interruptions

6 The Siren might be tried in a metallic cylinder, to learn if this will intercept its sound. If so, by making apertures in the Cylinder and causing it to revolve, it may be as possible to identify such signals as Revolving Lights

When a series of such experiments shall have given the comparative values of the above-named signals, and their ranges as found by Observers at Rest, the work would be incomplete unless it were extended to the conditions which occur in practice; and it should be tried, the observer being in a steam vessel, under way both in calm and rough weather. The Preliminary trials will have sifted out much uncertainty, and only those cases which give good promise need be examined; so that with a very moderate expenditure of money and labour, we should possess a complete collection of the Facts on which this Branch of Nautical Safety must be grafted”

Now surely here is, as I said before, a Programme of experiments, perfectly definite, presenting no serious difficulty, and not involving much expense. If I am mistaken in this notion I shall be very glad to be set right; for I must in a few weeks bring the matter again before the Board of Trade, and shall be sorry to give any suggestion which may mislead them. And let me remark that, so far from proposing one great connected system, this programme is quite fragmentary and might be worked out piecemeal: if you thought the whole of it too vast an undertaking, you might have advised the completion of even one part; say the Steam Whistle or the Siren. All our real knowledge has been built up, bit by bit.

You also ask me am I ready to take the charge and “responsibility of these experiments, or name one in whom I can trust. The first you must see would be in direct contradiction of the Second paragraph which proposes what I believe to be the only plan that can lead to any practical result. The Director must be always on the spot, (which must be one commanding a sea range) to avail himself of any sudden fog; he must also be accustomed to command sailors who are the fittest agents for the work, and who may not be easily managed by Civilians. As to the second alternative I shall not volunteer it; were I asked by the Board of Trade to name a man, I would say, ask the Hydrographer, Admiral Fitzroy or any of our renowned Arctic Voyagers, and they will find not one but several perfectly competent for all we want. If you doubt this, point out to me any specific point in these agenda, which you think a clever Lieutenant is not able to manage.

Remember that we (the Committee) have nothing to do with the Board of Trades application to the Trinity House. Our commission is to the former, and we did not understand it as authorising us to do more than mention to them the defective state of our knowledge about fog-signals, and suggest the necessary experiments to improve it. The course which they took to carry this out, is doubtless what they thought most likely to give a satisfactory result; but it remains to be seen whether they are satisfied with that which has been obtained. Their applying to the Trinity Board shews that they believe this Body has the Funds and the Power; perhaps also the Obligation to such a task; the Will only seems wanting.

Whether they will make another application in this quarter, or seek some other for cooperation, I have no means of conjecturing; but some way or other this work must be done. Till it is done, no general system of Fog-signals has a chance of being established and of course Wrecks and Deaths will continue on the old scale. Even since your first letter⁷ to me the Cunard packet has been nearly lost as the Anglo Saxon⁸ was a few months before; and I think with dismay on what will too surely happen this winter, aye and many more, if they that ought to provide the remedy look helplessly at the difficulties in the way and say with the sluggard, “there is a Lion in the path!”⁹ They may hap to find one there, and a perilous Beast he will prove, if any agitator takes up this affair in the Times or in the House of Commons.

You mention that the Trinity Board had been engaged with experiments on these signals: do these add any thing to the facts given in the blue book on Lights and Beacons¹⁰, and if so are they published or procurable?

Ever yours Dear Faraday | T.R. Robinson

Dr Faraday