altmarius

cultură şi spiritualitate

Volcanoes have long fascinated people. They have know how dangerous they can be, but throughout history many have tried to figure what causes them. Here is the explanation given by the medieval scholar Albert the Great.

Mount Etna eruption - photo by Alessandro Rossi / Flickr

Mount Etna eruption – photo by Alessandro Rossi / Flickr

Albertus Magnus (c.1200-1280) was a German friar and later bishop who is best known for his scholarly work, writing on dozens of topics from zoology to love. He is considered patron saint of natural scientists, and someone who wanted people to examine things through experimentation and investigation.

Around the middle of the thirteenth-century he wrote On the Causes of the Properties of the Elements, where he discussed the nature of the earth. He took a look at various questions, such as what causes mountains and valleys (he believed they were formed by earthquakes), and after judging the opinions of his predecessors, offered his own analysis. Towards the end of his book he wrote about volcanoes, beginning with noting the most famous one in Europe, Mount Etna, which lies in Sicily.

There is a volcano like it in many places. For there was one that was in the province of Swabia that burned for many years from the fire that shepherds made on it and then later it was extinct, as in our times Etna is almost completely extinct. And similarly there is a burning mountain near Liege, and when the rain trickles down upon its edges, smoke rises from it as if from a furnace. 

According to Albert, you needed two materials coming together in order to generate the fires underneath the earth – sulfur and naphtha. He describes how the former is a mineral that can be commonly found int the earth:

For sulfur burns underground easily either from the movement of the earth’s vapor, as fire is generated in a cloud, or from the motion and friction of the wind that has entered the ground through certain hollows, or even from the fact that the heat pressed into the ground by the sun’s rays is concentrated on one place by the surrounding cold, and then it kindles the materials found in that place.

Then he describes the second material, which was used in medieval warfare to cause fires:

For naphtha is a kind of pitch that is found in Persia, which has a glutinous and vicious fattiness that is very sticky and is somewhat like the lees of oil. When it is mixed together with sulfur, it becomes inflammable, and its fires adhered in an amazing fashion to whatever it is thrown against, and it can only be extinguished if the whole is covered at the same time.

 Illustration of Mount Etna as observed by the author in 1637. From Athanasius Kircher's Mundus Subterraneus, 1664.


Illustration of Mount Etna as observed by the author in 1637. From Athanasius Kircher’s Mundus Subterraneus, 1664.

Albert believed that these materials created hot springs, where they would continuously heat the water. According to him, the water would be unable to extinguish these fires. Meanwhile, on land, this combination would create a volcano:

For the material cause it that earth is sulfurous and mixed with oily naphtha, and the efficient cause is a vapor that is distributed in the ground and is unable to emerge. And because the sea water obstructs the ground’s pores and openings, for this reason it burns more quickly near the sea than it does elsewhere, and it burns as long as the matter has not been consumed, and it may burn for many years or perpetually if it happens that the matter is continuously replenished. And because a great deal of naphtha has been absorbed by certain rocks, when they are burned they remain very porous and light and float on the water, as pumice does.

Albert the Great’s book On the Causes of the Properties of the Elements, has been translated by Irven Resnick and published by Marquette University Press. Click here for more details.

See also: First historical evidence of a significant Mt. Etna eruption in 1224

See also: Volcanoes and the Climate Forcing of Carolingian Europe, A.D. 750–950

Vizualizări: 68

Adaugă un comentariu

Pentru a putea adăuga comentarii trebuie să fii membru al altmarius !

Alătură-te reţelei altmarius

STATISTICI

Free counters!
Din 15 iunie 2009

199 state 

(ultimul: Sint Maarten)

Numar de steaguri: 263

Record vizitatori:    8,782 (3.04.2011)

Record clickuri:

 16,676 (3.04.2011)

Tari lipsa: 43

1 stat are peste 600,000 clickuri (Romania)

1 stat are peste 90.000 clickuri (USA)

1 stat are peste 40,000 clickuri (Moldova)

1 stat are peste 20,000  clickuri (Italia)

2 state au peste 10.000 clickuri (Franta,  Germania)

6 state au peste 5.000 clickuri (Olanda, Belgia, Marea Britanie, Canada, UngariaSpania )

10 state au peste 1,000 clickuri (Polonia, Rusia,  Australia, IrlandaIsraelGreciaElvetia ,  Brazilia, Suedia, Austria)

50 state au peste 100 clickuri

24 state au un click

Rating for altmarius.ning.com 

altmarius.ning.com-Google pagerank,alexa rank,Competitor

DE URMĂRIT

1. ANTICARIAT ALBERT

http://anticariatalbert.com/

2. ANTICARIAT ODIN 

http://anticariat-odin.ro/

3. TARGUL CARTII

http://www.targulcartii.ro/

4. PRINTRE CARTI

http://www.printrecarti.ro/

5. MAGAZINUL DE CARTE

http://www.magazinul-de-carte.ro/

6 ANTICARIAT PLUS

http://www.anticariatplus.ro/

7. DEPOZITUL DE CARTI 

http://www.calinblaga.ro/

8. CARTEA DE CITIT

http://www.carteadecitit.ro/

9. ANTICARIAT ON-LINE
http://www.carti-online.com/

10. ANTICARIATUL DE NOAPTE

 http://www.anticariatuldenoapte.ro/

11. ANTICARIATUL NOU

http://www.anticariatulnou.ro

12. ANTICARIAT NOU

https://anticariatnou.wordpress.com/

13. ANTICARIAT ALEPH

https://www.anticariataleph.ro/

14. ANTIKVARIUM.RO

http://antikvarium.ro

15.ANTIKVARIUS.RO

https://www.antikvarius.ro/

16. ANTICARIAT LOGOS

http://www.anticariat-logos.ro/

17. ANTICARIAT.NET

http://www.anticariat.net/informatii-contact.php

18. TIMBREE

www.timbree.ro

19. FILATELIE

 http://www.romaniastamps.com/

20 MAX

http://romanianstampnews.blogspot.com

21. STAMPWORLD

http://www.stampworld.com

22. LIBMAG

https://www.libmag.ro/oferta-carti-polirom/?utm_source=facebook-ads-7-99-polirom&utm_medium=banner-facebook&utm_campaign=7-99-polirom-facebook&utm_content=new-3

23. DAFFI'S BOOKS

https://www.daffisbooks.ro/

24. MAGIA MUNTELUI

http://magiamuntelui.blogspot.com

25. RAZVAN CODRESCU
http://razvan-codrescu.blogspot.ro/

26.RADIO ARHIVE

https://www.facebook.com/RadioArhive/

27.EDITURA UNIVERSITATII CUZA - IASI

http://www.editura.uaic.ro/produse/colectii/documenta/1

28. EDITURA ISTROS

https://www.muzeulbrailei.ro/editura-istros/

29 ORIZONTURI CULTURALE

http://www.orizonturiculturale.ro/ro_home.html

30. SA NU UITAM

http://sanuuitam.blogspot.ro/

31. MIRON MANEGA
http://www.certitudinea.o

32. NATIONAL GEOGRAPHIC ROMANIA

https://www.natgeo.ro/revista

33. KORUNK

http://ideakonyvter.ro/53-korunk

Insignă

Se încarcă...

Anunturi

Licenţa Creative Commons Această retea este pusă la dispoziţie sub Licenţa Atribuire-Necomercial-FărăModificări 3.0 România Creativ

Note

Erfolgsgeschichte Taunusbahn

Creat de altmariusclassic Sep 13, 2013 at 11:02am. Actualizat ultima dată de altmariusclassic Sep 13, 2013.

Schnell und Steiner

Creat de altmariusplus Iun 19, 2013 at 1:59pm. Actualizat ultima dată de altmariusplus Iun 19, 2013.

Grosse Kunstfuehrer zum Schnell &Steiner

Creat de altmariusclassic Dec 21, 2012 at 6:55pm. Actualizat ultima dată de altmariusclassic Dec 21, 2012.

Hermann Hesse -bucher

Creat de altmariusscience Nov 7, 2012 at 5:47pm. Actualizat ultima dată de altmariusscience Nov 7, 2012.

Grosse Kunstfuehrer zum Schnell & Steiner - 1

Creat de altmariusclassic Oct 8, 2012 at 7:52pm. Actualizat ultima dată de altmariusclassic Oct 8, 2012.

Neuerscheinungen zum Schnell &Steiner - 3

Creat de altmariusclassic Oct 8, 2012 at 7:50pm. Actualizat ultima dată de altmariusclassic Oct 8, 2012.

Neuerscheinungen zum Bohlau - 1

Creat de altmarius Aug 29, 2012 at 7:30am. Actualizat ultima dată de altmarius Aug 29, 2012.

Neuerscheinungen zum Schnell & Steiner - 2

Creat de altmarius Aug 29, 2012 at 7:26am. Actualizat ultima dată de altmarius Aug 29, 2012.

Neuerscheinungen zum Schnell & Steiner

Creat de altmariusplus Mar 14, 2012 at 3:01pm. Actualizat ultima dată de altmariusplus Mar 14, 2012.

Grosse Kunstfuhrer: Maribor

Creat de altmariusconcurs Feb 22, 2012 at 1:08pm. Actualizat ultima dată de altmariusconcurs Feb 22, 2012.

© 2020   Created by altmarius.   Oferit de

Embleme  |  Raportare eroare  |  Termeni de utilizare a serviciilor