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[Jan. 



1882. 



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making r 



<3\\x Corrr£(pontirnrf Column* 



CHINESE CALCULATION. 



[DuRi.NG my first visit to America, in the winter of 1873-71-, a 

 Cliinese calculating miiu pave some remarkable proofs of the 

 rapidity with which the persons of )iis profession in China can 

 execute some of tlio common processes of calculation. His rapiditv 

 in exccntin}; long sums, or what with most would be long sums, in 

 addition, was remarkable. A scries of numbers, each of fom- digits, 

 were named to him as fast as the}- could be entered by a clerk, 

 and when the last of some thirty had been called out, he was told 

 to add them together. " It is already done," he said, naming the 

 total. When the numbers as entered by tlie clerk had been care- 

 fully added together, it was found that the total so named was 

 correct in every figure. It seems to me that there is something in 

 this feat which, though akin to the power some of our banking 

 clerks possess of adding in a single operation numbers of four digits, 

 yet so far surpasses that ])ower as to indicate the use of some 

 entirely different .system of arithmetical training, for I am given 

 to understand that what the Chinese calculator did. though it 

 Bcenicd so remarkable, fell far short of what many Chinese com- 

 puters could do. In fact. I was told he was only an ordinary com- 

 puter. Can any of our readers give any account of Chinese arith- 

 metic, or of theii' processes of rapid calculation ? — Ed.] 



MIND-DOCTORS. 



[224] — What JloliJre ridiculed in the doctors of his age is true, 

 to some degree, of the mind-doctors of the present time ; there is a 

 tendency among them to tlircatcn all maimer of evil consequences 

 from quite ordinary and familiar symptoms, unless their aid is quickly 

 called in. It occurs to me, by-thc-way (my momentary forgetfulness 

 on the point is one of the slight symptoms in question, and not, I 

 venture to assure myself, a sign of ajiproaching mania), that in 

 " Monsieur de Pourceaugnac," Moli^re lias satirized the verv ten- 

 dency with which we are here specially dealing: — " Qu'aiiisi no 

 Hoit," 8ay.s the First Doctor to the Second, speaking of the unfor- 

 tunate Dc Pourceaupnnc, "ponr diagnostique incontestable de ce 

 quo jo vous dis, vous n'avez (pi'il considercr ce gr-and scrienx quo 

 vous voyez, cette trisfessc aceompngnee de craintc et de defiance, 

 sigiies jiathognomoniqtics et individucls de cetto maladio, si bicn 

 marquee chcz le divin Hippocrate; cette physionomie, ces ycux 

 rnnges et hagards, cette grande barbe, cetto habitude du corps, 

 menue, gr^le, noire ot vclue, les(|uel8 signcs le deuotcnt tres- 

 afTect^ de cette maladic, j)roci!dantc du vice des hypocondres; 

 laquellc maladie, par laps ue temps. n<ttnrali.sfe, cnvieljie, habilui'e 

 et ayant pris droit de bourgeoisie chez lui, ponrroit bien degenerer 

 ou on manic, ou en phthisic, ou en ajioplexie, ou memo en fine 

 fr^ncsie et furenr. T(mt ceci suppose, puisqu'unc maladio bien 

 connuc est il derai gu<'-rie, car, vjnoti nulla est curalio iiiiirbi, il no 

 vous sera pas difficile de convcnir des remides que vons devons 

 faire h, monsieur," and so forth. Ceuebki'm. 



8EA SERPENT, OK SKAWEED :- 



[225] — If I am rightly inforniofi you are a believer in the sea 

 Bciiient. Tlie following extract from a daily |>a|icr may serve to 

 change your ideas on that subject ;■ -''A giKid wa «or|icnt story — 

 rntln!r lictter than those which are often published about this time 

 <»f year — comes from I^tadras, in the shajie of reminiscences of 

 Captain Taylor when lying at anchor in Table Hay some years ago. 

 One day an ' cnonnous monster,' about a hundred feet in length, 

 was seen advancing with snake-like motion round (Jreen Point into 

 the harbour. The head appeareil to be crowned with long hair, snd 

 the keener sighted amongst the obwr\-er» could see the eyes and 

 distinguish the features of the monster. The militarj- were called 

 out, and after peppering the object at a distance of five hundred 

 yards, and making several |)alpal>le hits, it was observed to become 

 i|uite still, and boats ventured off to complete the dist ruction.^ The 

 ' sea serpent ' proved to be a mass of gigantic seaweed, which had 

 been niululated by the ground swell, and had become quiescent 

 when it reached the still waters of the bay. Probably if marimrg 

 wonld attack the ' monster ' in the same manner whenever it is 

 seen, we should hear little more of the sca-serj)eiit." — 1 am, sir, 

 yours &c.," J. DAWKI^s. 



[Mr. Dawkins appears to think that we have never heard of sea 

 weed being mistaken for sea serpents. The following extract from 

 an essay on Strange Sea Creatui-es, p. 223 of " Pleasant Ways in 

 Science," may change his views in that respect ; — " Wien the 

 British ship Brazilian was becalmed . . . Jlr. Ilerriman, the com- 

 mander, perceived something right abeam, about half a mile to the 

 westward, stretched along the water to the length of about 25 or 

 30 feet, and perceptibly moving from the ship with a steady, sinaous 

 motion. The head, which seemed to be lifted several feet above 

 the waters, had something resembling a mane, running do«ii to the 

 floating portion, and within about 6 feet of the tail, it forked out 

 into a sort of double tin. Mr. Herriman, his first mate Mr. Long, 

 and several of the passengers, after surveying the object for some 

 time, came to the unanimous conclusion that it must be a sea- 

 serpent. As the Brazilian was making no headway, Jlr. Herriman, 

 determining to bring all doubt to an issue, had a boat lowered down, 

 and taking two hands on board, together with Mr. Boyd, of Peter- 

 head, near Al>crdeen, one of the passengers, who acted as steers- 

 man under the direction of the captain, they approached the 

 monster. Captain Herriman standing on the bow of the boat, armed 

 with a harpoon to commence the onslaught. The combat, how-ever. 

 was not attended with the danger which those on board appre- 

 hended ; for, on coming close to the object, it was found to be 

 nothing more than an immense i)iecc tif seaweed, evidently de- 

 tached from a coral reef, and drifting with tlie current, which sets 

 constantly to the westw.ard in this latitude, and wliich, together 

 «-itli the swell left by the subsidence ot the gale, gave it the 

 sinuous, snake-like motion." 



As a mere matter of detail, it may be remarked that there is 

 some difference bctw-een the distance of half a mile in this case, 

 of 500 yards in the other case, and in yet another case of a sea 

 weed sea serpent 800 yards, and the distance of 200 yanis at which 

 Captain M'Quhac, and other officers of the frigate Dwdalus, saw 

 what they st.ited to be " beyond all question a livinganimal, moWng 

 rapidly through the water against a cross sea and within five points 

 of a fresh breeze, with such velocity, that the water was surging 

 against its chest as it passed along at a rate jirobably of ten miles 

 per hour." Captain M'Quhae would not go after his seaweed 

 because he saw ho had no chance of overhauling it, so that for sea- 

 weed, travelling against the wind, it was tolerably active. Albeit 

 Mr. Dawkins will not find a word in the essay above-named imply- 

 ing that we believe in the sea serjient. A paddling, long-necked 

 sea creature, probably akin to the i'lcjiosniirH.*, seems suggested 

 by that portion of the multitudinous evidence relating to supposed 

 sea serpents which is trustworthy. Such a creature would not bo 

 a sea serpent, however. — Eo.] 



COLD SATURATED SOLUTION.— MARINE BOILERS. 



[226] — In answer to query 185, Thorjx!, in Jotoii. Chem. Soc. for 

 October, 1881, gives a method for estimating total salts in watei-. 

 In the same .lournal. Page & Keightley [2], X 5t>G, give amounts 

 of nitrate and chloride of K. and Na. in cold saturated solution. 

 Can find no reference to methods in DiV. Chew.. If Messrs. G. & 

 S. want a method for separate salts, there is no better way th.-ui 

 adding excess of salt, heating and shaking, then cooling to 60* (this 

 applies equally for common salt) ; orjif salt less soluble in hot water, 

 saturate the solution at a lower tem]>eniture, and let it rise to 60° 

 Then take 250 c.c. and make volnmetric analyses. W. G. must be 

 wrong in assuming that grease is jiresent in boiler crust. Dust, or 

 anv substance that will not wet, n.akc water sj>heroidal. 



C. T. B. 



