148 



NATURE 



\yune 15, 1876 



using the needle was, it must be confessed, rude enough. The 

 passage in the treatise * De Utensilibus ' contains one particular 

 which is very obscure, as Neckam informs us that when the 

 needle ceased moving it pointed towards the east {donee cusp's 

 aetts respieiat orientefJi) ; and as all the manuscripts agree in this 

 reading, and it is glossed by est, this must be the intention of the 

 vriter. I know no way of explaining this, unless it be by the 

 supposition that as in the twelfth century, the East was the grand 

 object of most voyages from this part of the world, an attempt 

 had been made to improve the magnetic needle, by adding to it 

 a limb at right angles, which should point to the east when the 

 needle itself pointed to the north, andthatthiswas what Neckam 

 called the cuspis acus. Between this and the date — whatever it 

 may be — of the poem, also quoted in my note on the passage of 

 Neckam, which contains the first allusion to the mariner's com- 

 pass in the thirteenth century, an attempt had been made to 

 facilitate its use.' This was done by thrusting the needle through 

 some substance which would not sink, and placing it upon the 

 surface of water. Guiot de Provins, the author of the poem 

 alluded to, calls this substance ^fesiu, a stick or straw (the Latin 

 festuea). The mariners, he tells us, have a contrivance depend- 

 ing on the magnet, which cannot fail. The magnet, he adds, is 

 an ugly brownish stone, to which iron is attracted. 'After they 

 have caused a needle to touch it, and placed it in a stick, they 

 put it in the water, without anything more, and the stick keeps 

 it on the surface. Then it turns its point towards the star with 

 such certainty that no man will ever have any doubt of it, nor 

 will it ever for anything go false. When the sea is dark and 

 hazy, that they can neither see star nor moon, they place a light 

 by the needle, and then they have no fear of going wrong ; 

 towards the star goes the point, whereby the mariners have the 

 knowledge to keep the light way. It is an art which cannot 

 fail.' According to another poet, the substance through which 

 the needle was usually thrust was cork. He tells us that ' the 

 mariners who went to Friesland, or to Greece, or Acre, or 

 Venice' were guided by the polar star ; but when at night, or 

 in obscure weather, it was invisible, they discovered its position 

 by the following contrivance: — ' They thrust a needle of iron 

 through a piece of cork, so that it is almost buried in it, and 

 then touch it with the loadstone ; then they place it in a vessel 

 full of water, so that no one pushes it out until the water is calm, 

 for in whatever direction the point aims, there without doubt is 

 the polar star,' The MS. in which this latter poem was found 

 is undoubtedly of the fourteenth century j but the poem itself is 

 evidently of somewhat older date of the beginning of that century, 

 cr not improbably of the century preceding. It is possible there- 

 fore that this rudely constructed marmer's compass may have 

 continued unimproved until the fourteenth century." ^ \lntro- 

 duclion, pp. 16-18.) 



1 In this interval we meet with another slight but very curious allusion to 

 the use of the magnetic needle for the purposes of navigation. Jacques de 

 Vitri, one of the historians of the Crusadec, who wrote about the year 1218, 

 says (" Hist. Hieros," cap. 89):— "Acus ferrea, postquam adamantem con- 

 tigerlt, ad stellam septentrionalem, quse velut axis firmamenti, aliis vergen- 

 tlbus non movetur, semper convertitur ; unde valde necessarius est navi- 

 gantibus in mari." 



2 This very curious poem, a sort of song, is preserved in a manuscript 

 formerly in the collection of M. Barrois, of Paris, and now in that of Lord 

 Ashburnham. It was first pointed out by M. Fr Michel, who printed the 

 portion relating to the mariner's compass in the preface to his " Lais Inedits " 

 (Paris, 1836). As this is now a rare book, 1 have thought it desirable to give 

 here the w hole passage, as a complement to the extracts given in the note 

 on p. 114 of the present volume. It is as follows ; — 



" La tresmontaine est de tel guise 

 Qu'ele est el fiimament asisse 

 Oil ele luist et reflambie : 

 Li maronicr qui vont en Frise, 

 liii Gres^e, en Acre, ou ea Venisse, 

 Sevent par li toute la voie ; 

 Pour nule riens ne se desvoie. 

 Tout jours se tient en uue moie, 

 Tant est de li grans li servisse, 

 Se la mers est enflee ou koie, 

 Jk ne sera c'on ne le voie, 

 Ne pour galerne ne pour bise 



Pour bise, ne pour autre afaire 

 Ne laist sen dout servise a faire 

 La tresmontaigne clere et pure ; 

 Les maroniers par son esclaire 

 Jete souveat hors de contraire, 

 Et de chemin les asscure. 

 Et quant la nuis est trop oscure, 

 S'esc ele encor de tel nature, 

 Ca I'aimant fait le fer traire, 

 Si que par forcha et par droiture, 

 Et par ruille qui tous jours dure, 

 Sevent le liu de son repaire. 



The following is the text of Neckam with the interlinear 

 gloss : — 



>"e une pere faut naute 



"Qui ergo vult habere navem, albestum habeat, ne desit ei 

 fu agiiyl mis 



beneficium ignis, -^ Habeat etiam acum- jaculo suppositam, 



turne _ e enunin aguyl poynt agardet 



rotabitur enim et circumvolvetur acus donee cuspis acus respieiat 



est tali modo i. ubi mariners 



orientem, sic que comprehendunt quo tendere debeant nautc cum 

 cinossura" [the cynosure, Kwoa-ovpa, or constellation popularly 



atapist de I'eyr tempeste cinossura 

 called Charles's wain] "latet in aeris turbacione, quamvis ad 

 achecement circle petit 



occasum nunquam tendat propter circuli brevitatem." ("De 

 Utensilibus," p. 114.) 



Mr. Wright adds : " The earliest account of the mariner's 

 compass, before known, was contained in the following lines of 

 a satirical poem, entitled the ' Bible Guiot de Provins,' composed 

 in the thirteenth century." (Barbazan, "Fabliaux," tom, ii. 

 p. 328.) 



" Un art font qui mentir ne puet 

 Par la vertu de la maniete, 

 Une pierre laide et brunete, 

 Ou li fers volontiers se joint, 

 Ont : si esgardent li droit point, 

 Puis c'une aguile i ont touchi6, 

 Et en un festu I'ont couch'd. 

 En I'eve le metent sanz plus. 

 Et li festuz la tient desus ; 

 Puis se torne la pointe toute 

 Contre I'estoile, si sanz doute, 

 Que i^ nus horn n'en doutera, 

 Ne jh por rien ne fausera. 

 Qant la mers est obscure et brune. 

 Con ne voit estoile ne lune, 

 Dont font h I'aguille alumer, 

 Puis n'ont-il garde d'esgarer ; 

 Contre I'estoile va la pointe, 

 Por ce sont li marinier cointc 

 De la droite voie tenir. 

 C'est uns ars qui ne puet failler." 



The language ot the last extract fully bears out Mr. Wright's 

 estimate of it as not earlier than the thirteenth century. 



Wm. Chappell 



The Dry River-beds of the Riviera 



Mr, H, T. Wharton's letter (Nature, vol, xiii., p. 448) 

 does not seem fully to explain the difficulty expressed by Mr. R. 

 E. Bartlett (Nature, vol. xiii., p, 406), a difficulty which is often 

 felt by many of the visitors to the Riviera, Mr. Wharton is quite 

 correct with regard to the Paglione, This stream has, I believe, 

 within the last few years been often in high flood, and has been 

 more than once within a foot or two of the top of the arches of 

 the bridge which Mr. Bartlett seems to think is unnecessarily 

 large. The Paglione, where it passes through Nice, is not, 

 however, a fair representative of the river-beds of the Riviera, 

 When the river-walls were built, which now retain the Paglione, 

 the river-bed was, in all probability, made much narrower than 

 it previously was, on account of the value of the land for build- 

 ing purposes, and only so much of the river-bed retained as was 

 necessary to carry away the water, so that the Paglione now 

 completely fills its channel when in flood. This is far from 



Son repaire sevent a route. 



Quant li tans n'a de clarte goute, 



Tout chil qui font cost maistrise. 



Qui une aguille de fer boute 



Si qu'ele pert presque toute 



En .i. pel de liege, et I'atise 



A la pierre d'ainiant bise ; 



En .i. vaissel plain d'yave est mise. 



Si que nus hors ne la deboute. 



Si tost com I'iave s'aserise ; 



Car dons quel part la pointe vise. 



La tresmontaigne est la sans doute." 



1 It was beiieved that the a&bestus, when once lighted, could never be 

 extinguished, and hence Neckam recommends it to be carried on shipboard, 

 that the sailors may never be without fire. 



' This rather obscure description of the mariner's compass, belonging 

 certainly to the twelfth century, is the earliest allusion to the use of that 

 important instrument in the middle ages. Alexander Neckam has, however, 

 given a rather fuller description of it in another of his books, the treatise 

 " De Naturis Rerum," lib. 2, c 89 (MS. Reg. 12 G. xi., fol. 53 v"> : " Nautae 

 etiam mare legentes, cum beneficium claritatis solis in tempore nubilo non 

 sentiunt, aul etiam cum caligine nocturnarum tenekrarum mundus obvol- 

 vitur, et ignorant in quem mundi cardincm prora tendat, acum super mag- 

 netem ponunt, qux circulariter circumvolvitur usque dum, ejus motu 

 cessante, cuspis ipsius septentrionalem respieiat." [Here the error about 

 pointing to the east is corrected.] 



