• No results found

eric EO,

N/A
N/A
Protected

Academic year: 2022

Share "eric EO,"

Copied!
11
0
0

Loading.... (view fulltext now)

Full text

(1)

i. N. y.

DISSERTAT10 GRADUALIS,

DE

REFRACTIQNIBUS

CRYSTALLI ISLANDIC.E,

Q.UAM,

CONSENT. AMPLISS. FACÜLT. PHILOSOPH.

IN REGIA ACADEMIA UPSALIENSI,

moderante

Mag. SAMUELE

DUR EO,

Frys. PROFESS. Reg. Et Ord.

Reg. Agad. Scient. Holm. Memb.

PUBLICE FENTILANDAM BXE1BET\

ALUMNUS REGI US,

eric u s malm,

SUDERMA NIVUS.

IN AUDITORIO GUST AVIANO DIE X. JUNIL

Anni mdcclxi.

HORIS ANTE MERID1EM CONSFETIS.

ü P S A L I JE»

(2)

■ ■

f* T.

N Islandk, quin & in Vermc-

kndia , deprenenditur lapis quidam pelhicidus^flilis coloris ex-

perSjfigur« utplurimum regularis*

qui vulgo Cryfiallttf Islandica dici

fölet, lic c I recentiores Mineralogi

ejus naturam penitius rimancea ad

illud genus iapidum referant, quod Spatum adpeilatur» Singularibus

omnino gaudec hiccc lapis p-rcprie- fatibus, quarum haec eft rariflima,. & quantum adhuc eonflat, huic unice comperens, quod obje&a per illum reprefententur ut plurimum dupllcia, quare ef järn llngva

noftra Dubbelften dicitur, Summa itaque fao jure cii- rioforum ocufos & animos dudum in fe convertit»

Neminem famen novimuf ante Erasmum Bartho- Ilnum, lllud certe Danlae decus, qui duplicem ejus re- fradionem , experiment!« Phyficis examinare co-

natus eft, quique ingeniofiflima lua Experiment a Cry- ßalli Jslandici Dis piaelaßici edrdlt Hafnl® 1670. Hase«

ce repetiit, accuratius inftitult & auxit llluftris Huge-

mus j atcjue Llbelio fuo De Dmine Parif. 1690, edlto,

in-

(3)

ffl

\

❖ ) 3 C ❖

#

inferuit, una cum tentamine, quo Ifta ex fua hypothe-

ft clrca propagationem lumlnis explicare annifus eft.

Denique in immortali fuoOptices opere Qvaift. XXV. p. m.

14 hane InuGtatse refra&ionis legem ulteriusdeferminavit

fummus Newtonus, quin & plura addid;t in ejus ex- plicationem, quae multa gaiidere videntur probabilitafe.

Hos fecufuruf duces in animum Induxi, qua fieri pot- eft perfpicukale, exponere mira hujus Cryftalli DisDIa-

claftici phsenotnena, quin &, quid de hypothefibus circa

illorum expiieationem exeogifatis, fit fentiendum, brevl-

ter perfpicere. Innoxios conatus, ut benigne interpre¬

teris, B, L. & lapfus in re tam abftrufa, faciilimos, be-

nevoie exeufes, etjam atque etjam rogo & obteftor.

§. II

Affediones bujus Japidis atque phaenomena, beic

memoranda funt:

1. Figtira cujus vis frufti regularis eft Parallele-

pipedl (Fig. i. ) obliquangull, quod nimirum con- ftat o&o angulis folidis, Quorum duo fibi invicem oppofiti funt atquales, & continentur tribus angulis obtufis, reliqui autem fex , binis angulis acutis Sc

uno obtufo; laterum parallelogramroorum fex fiujus lapidis anguli obtufi 101. gr. 52. min., acut! adeo

78. gr. 8« min.

2. Penicillus luminis incldens in}ejus fuperficiem,

dividitur in duos radios» quorum unus ex uftratic Dioptrices legibus refringitur, & quidem ita, ut finus anguii incidentke fit ad finum anguli refra&ionis, ut 5. ad 3. Alter autem radius refra&fone inufitata affi- citur, & cum priori, quando nimirum normalis eft, femper facit angulum 6. gr. 40. min. , qui tunc eft minimus, & fit major, quo major eft angulus inci«

A 2 den»

(4)

if } 4 C ❖

dendr, Urerqce ad akeram CryftalH fuperfictem fi-

rmliter fem per refrlngltur arque ad priorcm, adeo ,

ut radius eg t edlem 62t paraltelus radio incident. Än- gului hlc depréhenditur, a ut so piano bifecante an*

guium contentum fup er fielebus CM, Cö, aut in pia¬

no ifli parallele.

3, ObfervavJt Hilgen!us ($.10.) quod, fs in piano hoecc bifecante incident penic-ilios radiorum in fupcrficiem Cryftalii fere paralleles lateribus, feu in anguio 7}. gr. 20. min., in refringatur, ut una p&rs in directum prog-rediatur radio incident!«

4, Sit ADBC, fuperficies CryftalH, in quam radius incidit, & dupiiciter refringitur> C anguio.

rum foiidorum sd illasn fuperficiem maximus, feu in-

clinct Paratlelepipedum ad partens a C aver fam, &

a C damittafur CK normalis fareri oppofito FGEH spG

occurrens !n K, erit angulu* KCF 151. gr. 3»min. (a) Jun- (a) Si tres anptli (%. 2.) p läni ccnftituant unguium joTiåum AMLN, quorum dito MAL, LAN funt <e- quales, pf a puncto qitodam C in communi eorum interjectione AC, demittatur recta CE normalis ad

planum ter tri MA N\ atqiie jungantur puncta A E -y dito unguium MAN b i far i am jecari a recta Ä E.

A pun61 o C demittantur CB, CD, normales

In redas AM, ÅN, & ducantur red® £B, ED,

ob equale* anguios BAC, DAG (ex hyp,^) & ati-

guios ABC, ÅDC äquales (ex conflr.) & latus

AC commune utrfque triangulo ABC, ADC, e- rIt reda AB seqmlls red® AD, & reda BC aeqiia- Ils red® DC (26.IO unde quoque quadratum ex

* BC eft sequale quadratis ex BE, EC, Ar quadra¬

tum ex iiC eft asquale qutdratfs ex DE, EC,

( ex hyp. & 47» I, ) adeoque a b aiquaiibus demtis

scquaiåbus, erit qvadratum ex BE sequalc quadra-ta

(5)

-HHéhi V$^L

☆ ) s ( #

Junge K^> & in ea ftur.e KL, Ita ut argulus KC

A $ fit

ex DE, atque reda BE xqjualls redas DE» Hinc

cum in triangulis ÄßE, ADE funt latera AB,

BE asqualia iaferibus AD> DE, staue AE fit com¬

munis utrique, erit angufus BAE oequalis an gula

DAE (8. t.) » & adeo angulus BAD bifariarn feca-

tur a reda AE. Q» E. D.

Angulo MAN fic bifari am fe Bo, angulus ACE

Jaeile inveniri poteß. Ref. i, In friangulo A CD,

ex dafls angulls,& pro arbitrio afT^mta red3 AC>

c, gr, 15. quaere redarn AD.

2. In trlangulo A DE, ex datxs angulis, & reda

AD, qutere redarn AE.

t. In triangulo ACE, ex datis lateribus AC*

AE, & angulo AEC redo, obtinebitur ACE.

0

v

1. Sin. * 1. $2.

l/ij.

9' J »30968.

1.1700013.

i. R: Sin. ACD:: ACuAD~4. 10.489188U

I.R.Ziio. 0000000.

F. 4.»

I.

0,489*88 iL 2.Sin. AED;R::AD:AEzi5. !. R.m so. coooooo,

0

v

_J°*489?88i-

I.Sin.39.4.

9- 799495''

O / 0.68^9^0.:

3. AC:AEi:R;Sin. ACEZÜ9.3. LR.IZio. oocoooo.

10.6890930.

h IS*~ f* ä?Ö09t j.

9.51} do 17111.19.} »

Cw. I. Sin. ACD-t-1. Rad.—I. Sin. AED—I. Sin. ACE,

O *>

,

(6)

# ) 6 ( #

fit 6. gr. 40, min. Sit jam radius incidens ST nor¬

malis fuperffciei AB, ejus una pars in Cryflallo re¬

da progredietur, & occurret fuperficiei oppofitae in V absque refradione (2.) a V dueatur reda paralle-

ia redae KL, ipfique sequalis etjam furnarur reda VX, & ad easdern partes, & erit TX alter radius,

nimirum lnufitat;v refradlonis, erit enim angulus

VTX asqualis angulo KCL, ( 4. 1. ) feu <5. gr. 40.

min. ( 2 ).

Sin radius ST non fuerit perpendicularis fuperfi«

clei AB, dabitur refradio ordinata TV, ex data ratione finuum y. ad 3. <2.), A p.un&a V, ducatur quoque reda VX, ut priui, paraliela redac KL, & fiat sequalis illi,

ur habet NeWtonus, vel, propius forfan, sequalis ex-

ceflui, quo fecans anguli, quem format radius ufitate refraclus cum pcrpendieulo, fuperatur a fecante ejus-

dem anguli aeuti cum angulo 6. gr. 40. min-, dabit TX diredionem radii inufitatae refradionis.

Hujusmodi planum quodvis parailelum piano CKL,

dici potefi: planum perpendicularis refraciio ms, & plaga illa, quo fpedant redae KL, VX, a pundis K, V du-

dae dici poterit plaga inufitatez rcfractionis,

f. Objedum e. gr. pundum, vifum per hanc Cryftallum, adparef duplex, nam, cum objedum, quod

interveniente refradione adfpicitur , eo femper In loco fitum vldeatur, unde radii poftiiltimam refradionerndi-

vergunt, quo tempore inoculum fpedatoris incidunt ( Ax. VIII. O,)t. Newf.) & penicillus heic ab ob-

jedo progrediens in duos quafi feparatur, quorum

quivis diverfa gaudet refradione, adeoque radii ipfo-

ruin incidentes in oculum fpedatoris a duobus locis divergent, hinc in utroque illo, hoc elf duplex vide*

bitur objedum. Notandum tarnen, 1. Quod ita de-

pri-

(7)

& ) 7( #

prlpii poflit oculus» ut una imago laplde ipfo obte-

gatur, & tunc non nifi fimpiex videbitur objedum.

2. Cum imagir.es duplicis cujusvis pundi funt in pla»

no perpendicularis refFadionis, (2. 3.) eveniet, ut fi objedum fuerit Üneola reda, illa vero In eodem piano ponatur, videbitur firnplex, fed paullo longior

& verfus terminos dilutior, mm ambse imagines heic»

qua parfem, coincidunt. Si reda fit ilit piano nor-

?nalis» ert Bartholinus maxima elt I. diilanti» c. Experfm* inter Xf. däri locum imagines» j. quen- Ad»

dani In fuperficie Cryflalfi» in quo objedum pofitum

confpexlt fextuplum, nimirum putar penrciltum ex

objedo prodeuntem Sr riivifum rncidentem in fuper-

ficiem proximam Cry/talfi, in iila quafi conftituere

duo alia objeda, etjam emittentia penicillos divifos

ad fuperficiem fupremam. Sed cum hujus phsenome-

ni nullam faciant mentionem Hugenius Sr Newto-

nus, neque nos defedu cujusdam rnajoris Sr regula-

ris lapidis, iflud repefere potuerlmus* quin Sc cum

aliis notis vix convenire videatur, ideoque uiferiori inquifittoni erit relinquendum.

6. Sit CGHF fFig. 3.) planum perpendicularis

refradionis , Sr IK radius normaliter incidens, cujus

una pars refringatur, Sr occurrat haft in M, radii VK> SK ab utraque parte incidentes in angulis cequa- libus ita refringuntur, ut occurrant bafi in T,, X in

«qualibus diftantiis a pundo M.

7. St duorum hujus Cryftaüi fruftorum unum fub altero ita collocetur, ut plana perpendicularis re¬

fradionis fint inter fe paraflela, radii, qui in fupe-

riori Cryflallo uftfata raftcne refringuntur, iidem

in alterius (uperficiebtis refrinßuntur ufitate, qui ve¬

ro in fuperiori Cryftallo inufitata ratione refringun¬

tur»

(8)

3 S f &

tti 5 tth quoqtie refringantör iri alfeHus fuperficlebus.'

g. Si alterutrum fruftum convertafur > ut planum

.

perptfnilicularis refraétionis in ipfo fiat normale ph«

no perpendicularis refradlicnfs in altero# jam radii, qui in primo refringuntur ufltata ratione, in altera refringi deprehenduntur inufitata ratione, qui vero in priori refringuntur inufitata ratione, in altera re¬

fringuntur

4

utkate,.

p. Si binarum CryftaHorum plana perpendleu-

laris refraélionis fint inter fe rjeque ad pefpendicu- lum, neque parallefa pofita, tunc uterqué radiorun»

pr im sm Cryfiallum pertranfeuntium, in ingreffu fe¬

cund« Cryilalli Iterum in duo£ radios dividitur.

§. Hl.

Iniifjtatam hujus Cry'ftalli refraftlonem, nemo an-

te Hugenium, quantum con/lat, explleare adgreffus e/l.

Qyum vero häec nttatur hypothefi, ab eo adfurnta cir¬

ca naturam luminis, quam ad phtsnornena explieanda

non «/Te. futficientem , pluribus dernonftravit Newto-

rius (Opt. Queeft. XXVffi. ) illa rnulus exponenda non

immorabimur, pr«eipue, cum ipfe Hugenfus efcämmsns

cnines circumftantias hujus refraétfonis, anceps hseferit»

& fa/Tus fit, fe nondum inveniffe, qua; ipfi p offen? fa-

cere fatis, Quin & Ne wton o videatur , hane rem mil- los omnino habere pofje explkatus, [i lumen nihil fit aliud

quam preßus quidam bei mortis per eit terem prepagatus, (i. c. p. m. 149«) Explicationem vero hujus phaencmenl, kmge felicius, nollro quidern judiciö, tenfavicNewtdbus,

quam ifaque paucis propenemus: Cum radii, qui in-pil«

ina Cryitalii fuperficie refringuntur-ufirate veh inufirate,

in omnibus aliis fimiüter refringsnrur y dum plana-per- pendicularis refra&ionis funt paralida, necefTe eft ,radhs.

lu-

(9)

luminfs inefie congenita«* quandam difFeremiam, qu®

eadein manet in omnibus hifce refradionibus. Qvod ve- ro hi radil non natura fua fint diuerfi, exinde confiare videtur, quod, dum plana perpendicularis refradionis firnt ad angulos redos pofifi, radii, qui in prima Crydallo ufi-

täte refrlnguntur, in altera inufitate relringantur, & vice verfa» adeo, ut diverfitas refradionis foium pro venire vi¬

deatur ex diverfo fitu laterum radiorum ad plana perpen¬

dicularis refradionis. Unde inquovis peniciiio, concipl pofTunt quatuor latera, quorum duo ex adverfo oppofita faciunt, ut radtus tories refringatur ratione inufitata,quot!es

alterutronn eorum converfum 6t adCryftalli plagam inufi-

tat« refradionis; reliqua autem duo, licet alterutrum eo¬

rum convertatur ad plagam inufitataj refradionis, non fa¬

ciunt, ut radlut alia, quam ufitata, ratione refringatur. JSt

haec videtur efTs illa radiis vel radiorum Jateribus oppofitis

congenita Proprietät ex qua pendet inufitata refradio, cu¬

jus funt expertia altera bina latera. Si vero ( n. 9.) Cryftal-

lorum plana perpendicularis refradionis in angulo obliquo

ponantur, jam duorum radiorum e prima Cryftallo emer- genHum uterque dividetur infuper in binos radios, in in»

grefTu fecundse Cryfialb, nam radiofl, ex quihus uterque ra¬

diorum ifiorum conftaf, babebitnt limiliter alia latera fua InufkatiS refradionis,, ut didum de prioiibus.

j. IV.

Haec funt praeefpua, quse multa cum fagacitate defexe-

runt prsedannflimt PiyOi,& commentatifunt deraris Cry-

ftall» Islandfcte refradsooibus; quseque eum preecipue in n-

n**m, i icet pro ratione circumfianriarum, perbreviter adtu- limus, ut mtrabili* na urae cuivis eo melius pareant, atque atteriH & réligicfi operum divinorum fptdatores magis magisque iiifiammentur &d perquireiidaa fciiaS piures abs-

B con-

(10)

#)«*(£

condiüas tam hujus lapidis, quam ipfius luminfs proprie-

fites, ut eo msgis extenrlattir genuina Scientia Phyiica 3

Talus publica promoveatur , & arue omnia

femper celebretur,

SUMMI CONDITORIS GLORIA.

CLARISSIMO DOMINO CANDIDATO.

AMICO HON ORAT1SS1MO.

b

vn n1? cyj nn

:'ö nana aia ®M >yn

nKin airo"? "nsT

:nm aenn nyta ania bxw ran ©7 Vaa rrbtr -frys r«

•tpw xnpa an :ny© na» sw Vnd

Andreas Leonhard Lindckeen.

(11)

References

Related documents

The evaluation was based on a comparison of crime rates in an experimental area (the neighbourhood watch pilot project area) and three control areas in which neighbourhood watch

Although a recent meta-analysis found that the two main types of family-based programs, general parent education (i.e., home visiting programs aimed at improving health and

However, studies of higher methodological quality found little evidence that mentoring reduced reoffending, suggesting that inadequate control of pre-existing differences

The main selection criteria were that the evaluation should be based on voluntary treatment programmes that aimed to reduce drug use (e.g. methadone maintenance, detoxi- fication,

The anti-bullying initiative in the Netherlands was inspired by the Olweus programme (Fekkes et al., 2006, p. The programme was specifically designed to tackle bullying behaviour

The treatment group (n=62; only those who completed the programme) and the comparison group were matched on a number of features including age at first violent offence, total

After identifying 34 studies that met a series of highly stringent in- clusion criteria, the analyses indicated that: (1) self-control improve- ment programs improve

At 18 month follow up period, the treatment group had a lower percentage of general recidivism than the control group with not significant differences between the two groups