Cwrr y Llen
Subtitle: Ysgrifau Syml ar Faterion Gwyddonol
By: Gan Gwilym Owen, M.A., D.Sc., Athraw mewn Athroniaeth Naturiol yng Ngholeg y Brifysgol, Auckland, N.Z.
Publisher: Hugh Evans and Sons
Published: 1914
Place of publication: Liverpool
Language: wel
Format: Hardcover
Number of pages: 142
Subjects: Physics; Physical science
First sentence: Pe gofynnid y cwestiwn, yn yr oes hon, Beth yw Goleuni, yr ateb cyffredin a roddid fuasai mai rhywbeth yw goleuni yn ymsaethu gyda chyflymdra mawr allan o wrthrych goleu, ac yn peri gwelediad drwy ei effaith ar y llygad ; ac mor bell ag y mae yn myned, gellir dywedyd fod yr ateb yn hollol gywir.
Description: A popular book about physics written in Welsh. It includes discussions of light, colour, gravity, planetary motions, air and gas pressure, the nature of matter, electricity, electrons, X-rays, the wireless telegraph, radium, radioactivity, the transmutation of the elements, and the age of the Earth. It has several black and white line figures and photographs.
Notes: The author is Prof. Gwilym Owen (1880-1940).
Table of contents: pagenum: 3
class: chapter
title: At y Darllenydd; pagenum: 5
class: part
title: Cynhwysiad; pagenum: 7
class: part
title: Darluniau; pagenum: 9
title: Natur Goleuni
class: part
label: I; pagenum: 17
label: II
class: part
title: Deddfau Goleuni. I.  Adlewyrchiad; pagenum: 26
label: III
class: part
title: Deddfau Goleuni. II. Plygiad.; pagenum: 35
title: Athroniaeth Lliw a'r Enfys
class: part
label: IV; pagenum: 43
label: V
class: part
title: Dysgyrchiant; pagenum: 48
label: VI
class: part
title: Comed Halley; pagenum: 55
label: VII
class: part
title: Yr Awyr a'i Bwysau; pagenum: 61
title: Syniadau Hen a Diweddar ar Gyfansoddiad Mater
class: part
label: VIII; pagenum: 79
title: Trydan. I.
class: part
label: IX; pagenum: 85
title: Trydan. II.
class: part
label: X; pagenum: 96
label: XI
class: part
title: Darganfyddiadau Diweddar : Yr Electron. I.; pagenum: 101
title: Yr Electron. II.
class: part
label: XII; pagenum: 105
label: XIII
class: part
title: Pelydrau Roentgen; pagenum: 110
title: Pelydrau Roentgen eto
class: part
label: XIV; pagenum: 115
title: Y Telegraff Diwyfr
class: part
label: XV; pagenum: 120
title: Radium
class: part
label: XVI; pagenum: 125
title: Ychwaneg am Radium
class: part
label: XVII; pagenum: 130
label: XVIII
class: part
title: Trawsnewidiad yr Elfennau; pagenum: 136
title: Radium ac oedran y ddaear
class: part
label: XIX