George Eliots' notebook, p.18.

Move your pointing device over the image to zoom to detail. If using a mouse click on the image to toggle zoom.
When in zoom mode use + or - keys to adjust level of image zoom.

Date:1872 - 1880 (c.)

Description:Discourse on the 'Duration of Earth.'


Transcript:

"To maintain the present rate of radiation it would require the combustion of about 1500lbs of coal per hour on every square foot of the Sun's surface; & were the Sun composed of that material it would all be consumed in less than 5000 years." Crook, Probable Origin & Age of the Sun.

"The opinion that the Sun's heat is maintained by combustion cannot now be entertained.... It is now generally held by physicists that the enormous store of heat possessed by the Sun could only have been derived from gravitation. For example, a lb of coal falling into the Sun from an infinite distance would produce by its concussion more than 6000 times the amount of heat that would be generated by its combustion..... There are two forms in which gravitation theory has been presented: the first, the meteoric theory, propounded by Dr. Cheyer; & the second, the contraction theory, advocated by Helmholtz. The former has been now pretty generally abandoned for the [page 19] latter. According to a calculation of Helmholtz - suppose the Sun originally existed as a nebulous mass, filling the entire space presently occupied by the Solar System, & extending into space indefinately beyond the outermost planet, the amount of heat from the gravitation of this mass to an orb of the Sun's present size, would suffice for 20,237,500 years.

The limit of the Sun's heat, or age of its heat, must have limited the age of the habitable globe. All its geological history would be comprehended in this period. If the Sun derived its heat from the condensation of its mass, then it could not possibly be more than about 20,000,000 years since the Laurentian period. But twenty millions would be considered by most geologists to representing a comparatively small portion of the time since organic life began on our globe.

Here the theory clashes formidably ith geologhy. Take denudation. It is calculated from the river deposits, that to lower the country one mile would take fifteen million years. For even during the carboniferous period [page 20] more than a mile in thickness of strata was removed. But if the calculations of Geology supported by demonstrable facts are opposed to the theory that gravitation is the sole cause of the Sun's heat, where is the necessity of accepting this theory? Even if we could not conceive another cause, our inability of conceiving would not be conclusive as to the non-existence.

Croll suggests the collision of two bodies moving at enormous velocity as a possible origin of our Solar System - the heat generated producing nebulous expansion & being illimitable store of heat over & above that resulting from condensation to the present condition.


Timeline

The timeline shows resources around this location over a number of years.

1810s
Letter fragment
Letter fragment

An invitation to an unknown person to visit. Transcript: So come to us when ...

1840s
Portrait of Robert Evans
Portrait of Robert Evans

Robert Evans, Mary Ann's father, taken from the miniature by Carlisle painted in ...

1860s
Letter to Mrs John Cash, p.1 and 4
Letter to Mrs John Cash, p.1 and 4

Mary Ann is now living with George Henry Lewes and signs this letter M.E.Lewes. ...

1880s
Engraved portrait of Charles Bray
Engraved portrait of Charles Bray

Engraved portrait of Charles Bray, aged 72, by H. Adlard from a photograph. George ...

1910s
George Eliot, Adam Bede decorative binding.
George Eliot, Adam Bede decorative binding.

Illustrated edition by Gordon Browne. Publisher unknown. Printed by W and R Chambers ...

Share:


Donor ref:Nun. Lib. (49/11394)

Source: Nuneaton Library, Libraries, Heritage & Trading Standards, Warwickshire County Council

Copyright information: Copyrights to all resources are retained by the individual rights holders. They have kindly made their collections available for non-commercial private study & educational use. Re-distribution of resources in any form is only permitted subject to strict adherence to the usage guidelines.