Fiiu 3, 18S2.] 



• KNOV/LEDGE 



295 



erist, and the want of sncli an institntion was felt at the time of 

 the Tay-bridge accident. Liverpool has set a noble example to other 

 seaports in this respect, which is worthy of being imitated by the 

 important seaports in the North of England, and by the ports of 

 Leith and Dundee, in Scotland. — Tinies. 



EASY LESSONS IN BLOWPIPE CHEMISTRY. 



By LiKrT.-CoLONEL W. A. Boss, l.\te E.X. 

 Lesson n. 



HAVIXG made his blowpipe, the student must now make, or 

 provide himself with, a lamp, in the following manner : — 

 The solid or closed end of an old iron gas-pipe, from 2 to 2J inches 

 in diameter, price about 2d., is the lamp, and a very excellent one it 

 makes, as shown by my pupil M. Lombaxdi, of Argyll-place, Regent- 

 street. The wiek, a few strands of twisted cotton, held together 

 and supported at one side of the gas-pipe by a piece of zinc-foil bent 

 into the requisite shape, is now pat in its place ; and the fnel, con- 

 sisting of any combustible hydrocarbon which solidities on cooling, 

 as pure boef or mutton fat, old " composite" or other candle-ends, 

 cocoa-nut oil (from which glycerine has not been extracted), or all 

 these together, added, and melted by heating the side of the lamp 

 itself before the blowpipe by blowing the flame backwards on the 

 iron rim ; and here I must caution the aspiring blowpiper (or, as I 

 prefer to call him, '' pvrologist ") against demolishing his work at 

 tliis stage of proceedings by allowing the blowpipe-fiame to play on 

 the zinc-foil which he has jost made 1 The wick, about the thick- 

 ness of the end of a woman's little-firger, is best trimmed and cut 

 with an nnlinary pair of scissors, such as the American ones now 

 sold for 6d. a pair. 



fell tar, 1 teei sure, your working-men readers will admit that a 

 blo^\"pipe apparatus is by no means the expensive luxury it is thought 

 to be ; but the absolute necessity I am now about to mention, cer- 

 tainly does cost a little money, which will, I fear, somewhat strain 

 his liard-eamed and much-needed wages. I mean platinum wire, 

 for old ends of which, however, half-price is allowed by Messrs. 

 Johnson & Matther, Harton Garden. This should be about the 

 thickness of an ordinary horse-hair (I, myself, use it still thicker), 

 cut into lengths of 3 in., and rolled into a ring about i in. in 

 diameter, at one end. This is best effected by the ordinary " cage- 

 maker's pliers " of the ironmongers' shops ; but anyhow, this ring 

 must be carefally made, and as nearly a circle as possible, if only 

 constructed on a pencil-point ; unlike the slovenly figures recom- 

 mended in some books on the blowpipe ; some English works on 



chemistry even advising the use of a hook ^J , which they 



tell you to fuse into a glass-tube by way of handle ; to which piece 

 of lunacy, I can only say, " Good gracious ! " Here is a rough 

 figure of a " platinum wire support," the natural size and thickness. 



This wire is best held between the legs of a pair of ordinary 

 'watchmaker's pliers," kept together, when required, by a little 

 bi-ass picture-wire rolled round the shank, so that this wire *' strap- 

 ping" may be slipped up and down ; the " slipping up " closing the 

 pliers tightly on the platinum wire, and enabling them to act as a 

 handle for it ; the " slipping down" opening the legs, and enabling 

 them to act as pliers again. The pyrologist has thus not only a mere 

 handle for liis platinum wire, like the elegant ivory German ones sold 

 at Freiburg, but an instrument by which he can effectually clean and 

 straighten the latter for use. A mathematical pen also makes a 

 capital holder for plarinum wires. Now for my student's chemicals. 

 Messrs. Herring ,i Co., the wholesale chemists, of ALdersgate-street, 

 City (who, 1 dare say, have never heard of me or my blowpipes, 

 but, for all that, I am a pleased customer of theirs), sell the exact 

 kind of re-agent suitable for this part of my system of blowpipe 

 analysis for (5d.an ounce, or less if taken in quantity ; 2 ozs. lasted 

 me four years. It is called " Glacial Phosphoric Acid," and cast in 

 sticks. It is manufactured in Germany, and, 1 believe, contains 

 from 15 to 20 per cent, of soda, without which it could not be cast ; 

 but it acts as a poweri'ul acid before the blo«"pipe. 



It should be broken into small fragments and kept in a wide- 

 i^'juth stoppered bottle, as it is very deliquescent. To use it, shake 

 ;t some of the smallest fragments on a white porcelain plate turned 

 ijiside down, or any clean smooth surface. Make your wire-ring 

 T'd hot before the blowpipe, and, touching the smallest pieces, 

 ^'. 'oich will thus adhere to the ring, heat them very gently, that is, 



about half an inch in front of the blue blowpipe-pyrocone, along 

 ivith a few specks of oxide of manganese (of which two penny- 

 worth will last most people a life-time). When the oxide is dis- 

 solved, which it is thus very rapidly, a charming amethyst-coloured 

 •' bead " is the result. Now plunge the bead into the middle of the 

 blue pyrocone, and hold it there for half a minute; when with- 

 drawn, it will be as colourless as a bit of pure glass. This effect 

 may be repeated as often as desired. 



EFFLUVIA AND HEALTH. 



THE query of J. Maccinslane, No. 183, page 23-1, is probably 

 answered by one of the quaint and wise remarks of the late 

 Professor Brande, who, speaking of sulphuretted-hydrogen gas, said 

 that " it is not the stinking gas, but the bad company it keeps that 

 is so mischievous." 



It is well known to all who have worked at elementary analysis in 

 a laboratory, where this gas is much used as a general reagent, that 

 no mischief arises from breathing an intensity of stink that would, 

 probably, induce fatal disease if it came from a sewer. The same 

 applies to dissecting-room effluvia. In my student-days, in Edin- 

 burgh, we used to say that the above-named gas gave us an appe- 

 tite, but, if placed in a witness-box, I could not swear that this 

 theory may not have been invented to justify suppers at '' The 

 Rainbow." 



Had the bullock's blood used in Mr. Maccinslane's dye-house been 

 left in a sewer, and sown with germs of fungi, bacteria, &c., the 

 results would doubtless be very different, unless the other chemicals 

 there used are sufficiently volatile to poison the poison. 



W. Matoeu William.<. 



THE USE OF FLEAS, &c. 



THE query of " Amateur " reminds me of a, paper I wrote many 

 years ago, in which was revealed a discovery made during my 

 wanderings in Greece. I slept — or rather reclined — in the capa- 

 cious hovel of an Albanian farmer at Marathon, hard by the famous 

 battle-field. My bed was the clay floor of the farm-house, my bed- 

 fellows were my fellow tourist, our dragoman and horseboy, the 

 fanner, his wife and five children, besides our three horses, the farm 

 stock of poultrj-, and a population of the animals under considera- 

 tion, exceeding in number the possibilities of a census. 



During the night the childrea awoke at intervals, cryingpiteously, 

 and the fond mother, knowing why, picked them up severally, laid 

 them on her lap, and scratched thom liberally all over. After this 

 they slept for awhile in peace. Hereby was suggested my discovery 

 of the use of fleas to mankind. These people were not addicted to 

 washing, which is also the case with a large numerical majority of 

 the human race. The less washing the more fleas, the more et 

 cateras, and the more scratching. 



The unwashed majority of human beings require some substitute 

 for washing, in order to effect the necessary removal of the shrivelled 

 and effete epidermal cells. Scratching is such a substitute. But I 

 have shown above that scratching varies directly with the supply of 

 fleas and et caeteras, and inversely vrith washing. Therefore fleas 

 and et cateras benefit mankind as well as themselves, and the obli- 

 gations between the species are strictly mutual. Q. E.D. 



W. Mattieu Williams. 



FISH "SOUNDS." 



IN Dr. Andrew Wilson's very interesting paper on " Found 

 Links" (Knowledge, Jan. 6, page 195), "the suAmming- 

 bladder, air-bladder, or sound," are described as synonymous. 

 There is a small mistake here, a misunderstanding of fishermen's 

 technology, that may mislead some readers. The same mistake 

 occurs in' anatomical text-books. Dr. Wilson will readily nndcr- 

 stand the nature of the error by simply buying some " ood sounds " 

 from any fishmonger. They are regular articles of separate 

 commerce, salted by millions in Norway, and exported in small 

 barrels. 



He will find that the sound is not the air-bladder, but the aorta, 

 or chief blood-vessel of the codfish, laid open, and with some of the 

 larger branching vessels attached. This vessel, forming a stout 

 membranous bag, is attached by its edges to each side of the under 

 part of the spine of the fish, from which the Norse and Newfound- 

 land fishermen tear or rip it when they split the fish for salting. 



I have a theory of my own concerning the etymology of the 

 word, viz., that it is of Scandinavian origin, like the commercial 

 article, and is derived from Sondre, to sever or rip, from which we 

 also derive our word asunder. W. Mattieu Williams. 



