that Sir William Thomson chiefly finds fault, and he thinks th it would be an unspeakable improvement if every one of them ha its speed sextupled, and he would then apply the system of lor and short flashes to enable each light to signal its own number letter continually.

He proposes, secondly, that every fixed light should be disti guished by a rapid group of two or three dot-dash eclipses, the d to be of about half-a-second in duration and the dash three times a long as the dot, with intervals of light of about half-a-second betwee the eclipses of the group and of five or six seconds between th groups.

Sir William thus practically merges his first proposition into th second. He would quicken the speed of all revolving lights, an introduce rapid occultations into all fixed lights in order that the do dash system may be applied to both. It should be observed, that f the revolving lights he would make the flashes of light do the dut of making the long and short signals, while, for the fixed lights, h proposes that the occultations, or dark intervals, should be en ployed for the purpose.

The first thing that occurs to the nautical mind is that in th event of the adoption of Sir William Thomson's scheme, it would b necessary for all seamen to be acquainted with the Morse Alphabe which consists of twenty-six combinations of not less than two an not more than four long and short signs.

We are of opinion that in the present condition of education would be out of the question to expect any seaman to comm all these combinations to memory; it would be, for him, a mos difficult accomplishment, and can only be achieved at all b persistent application and continued practice in the use of th symbols. But it may be said it would not be necessary that seame should learn the alphabet by heart; it would be sufficient if the had at hand a card to refer to by which the signals might be rea off. We do not, however, think this plan would be agreeable t the mariner.

Again, the change would necessitate an alteration in all th published Lists of Lights and in all charts of the coast. The mariner would want to know what was the letter appropriated to

each lighthouse, and it would be necessary for that letter to be added whenever the light was described or referred to. This also would be source of inconvenience to seamen, and would not be welcomed by them.

Moreover, as there are only 26 distinctions available by the Morse alphabet, and as, according to Sir William Thomson, the number of lights on our coasts exceeds 600, it would be necessary to repeat the alphabet about twenty-four times in order to give every light a letter. It is difficult to see how confusion would be avoided in the case of the lights on the East coast of Ireland and those on the West coasts of England and Scotland; and there is no doubt that the lighting arrangements of the North coasts of France, Belgium, and Holland would be seriously interfered with if the proposed system were to come into operation on the British coasts.

Again, the mariner would also have to remember that sometimes the signals would be conveyed by means of long and short flashes of light, and sometimes by means of long and short intervals of darkness. In the one case, continuous darkness would be broken by flashes of light; in the other, continuous light would be broken by flashes (so to speak) of darkness. To mistake the one for the other of these two classes might be disastrous in the extreme, and to our thinking it seems that as the sailor's mind would be bent almost entirely upon making out the dots and dashes, he would be apt to confuse the two classes, and might substitute one for the other.

But assuming, for the sake of argument, that these preliminary hindrances to the application of Sir William Thomson's proposal could be all satisfactorily overcome, the question then arises: What practical advantages would the mariner derive from the special forms of distinction proposed? In the place of the present highly varied system, he would find all the lights perpetually bobbing and jumping, and each by its continual Jack-in-the-box movement, firing off the necessary groups of dots and dashes to signalise the letter which may have been appropriated to it. Sir William makes no provision for any other kinds of distinctions to be used, and would abolish the use of colour except for sectors for local purposes, so the mariner would see nothing but white

C

lights continually on the move. It is true that they will diff from the masthead lights of steamers under way, which appea to be one of the chief objects aimed at, but the anchor lig of a vessel rolling ever so little to the action of the waves is alway liable to be characterised by what may be termed occultation produced by the interference of masts, rigging, sails, smoke, stear or passing vessels, and although the occultations so produced mig not be regular, yet they might be sufficiently marked to cau considerable doubt in the mind of the seaman as to what light could be, and to involve a great loss of time in his endeavours find out.

But another great advantage which Sir William Thomson clain for his proposal is, that it will greatly facilitate the picking up of light in comparison with the means offered by the present syste of distinctions.

We have already shown that the adoption of the proposed syste would involve the shortening of the duration of the flashes them selves, even to such short periods as one second and half-a-secon and it is probably believed, on the other hand, that the increase frequency of their recurrence would obviate any inconvenien which might be caused by reducing the duration of the flash to su exceedingly short periods. But it must not be forgotten, that th construction of the optical apparatus of the revolving lights no in operation is such that it will not admit of the flash being reduce without a considerable loss in the intensity of the light. A flas of some seconds' duration sent through a panel of, say, a six-side apparatus, consists of a great amount of light gathered up into powerful beam; but in order to produce these rapidly recurrir flashes, the body of light falling upon the panel must be cut up in a great number of very small sections, and the light sent throug each section would be, in comparison with the large beam tran mitted through the entire panel of 60°, weakened in proportion to t reduction of the angle into which the light is gathered. But, besid this, a mechanical obstruction exists which would make it extremel difficult to apply the system of short and quick flashes to existin revolving lights. It would either be necessary to completely alt the optical arrangements (which would involve an enormo

expenditure), or the apparatus would have to be rotated so rapidly that one man would be chiefly occupied in winding up the clockwork, to say nothing of the inconvenience, risk, and wear and tear with which so rapid a velocity of the glass apparatus would be attended.

But, under any circumstances, the intensity and penetrating power of the light would be lessened by the adoption of quickly recurring short flashes. The mariner thereby would lose the power, and possibly the visibility of the light, for the sake of gaining the dot-flash system of distinctions. At times when the light would be most required, its intensity would be enfeebled, and through haze, rain, or snow, he might with difficulty make out faint blinkings, which it would require the most careful observation and thought to interpret. We ask our readers, the majority of whom know practically what is wanted, will they sacrifice intensity of light for the sake of a new code of distinctions? and would the mariner be assisted in picking up any given light by its change to rapidly recurring but enfeebled flashes?

But we have another point to make against the dot-and-dash system. What the mariner really wants is a light which immediately it is sighted proclaims to him its own individuality. This would not be the case with the dot-and-dash system of signalling, even though the Morse Code were as familiar to him as the letters of the alphabet. Sir William Thomson, on board H.M.S. Northampton, or his own comfortable yacht, would no doubt be in a position to devote all his attention to the minute observance of lights. In his letter to the Times he admits that when criticising the performances of some of the channel lights, his mind was free from navigational anxiety, and as a scientific observer he has devoted himself entirely to the question.

To Sir William Thomson the Morse Alphabet is "as easy as A B C," he can see no difficulty in reading the signals—his mind is full of it-and what is so simple and intelligible to him must, he appears to think, be equally comprehensible to everyone else. But we must remind Sir William Thomson that merchant sailors are not all scientific observers, nor able to sympathise with ingenious scientific theories. However competent the commanders and officers

of our great steamships may be to appreciate a complex system signalling, it must be borne in mind that the lighthouses of o coasts are also intended for the use of thousands of men to who the details of short and long flashes, the Morse Code, &c., wou be merely so many additional perplexing elements in the perfor ance of the business of their lives.

Imagine the master of a small trader, on a rough night, with his mi full of the hundred and one matters connected with the navigati of his vessel, yet anxious to assure himself of his position; wo he wish to add to his already burdened mind the task of deciphe ing the meaning of what would appear to him, at first sight, to a very rapidly blinking light. To do so he must give up for t time all thought about his ship; he must concentrate all 1 faculties on the light; he must find out first the number of flash or occultations in a given period, and must then decide which them are long and which are short; having after repeated observ tions satisfied himself on this point, he must then remember find out what letter is symbolised, and having accomplished th must then recollect or search out to what light the letter in questi is appropriated. And all this it would be necessary for him to at a time when the light was just showing above the horizo and he was in an anxious state of mind, wishing to verify position. We venture to think that practical seamen will regard t multiplication of the efforts necessary to determine the name o lighthouse as a fatal objection to the introduction of such a syst of lighthouse distinctions. If every nautical man had the Mo Alphabet at his fingers ends; if the signals could be conveyed w the greatest certainty and intelligibility; if the short flashes of lig retained the intensity which the longer flashes possess; if the mi of the sailor were in a state of absolute certainty as regards t "flashing" system and the "occulting" system; and lastly, the existing system of distinctions were so lamentably deficient to provoke the outcries of those who require to make use of t lights, and to lead to disaster, then we would be disposed to lo with more favour on the proposition of Sir William Thomson, a the necessities of navigation would, no doubt, call for its adopti if nothing better opposed it.