400:"}},"text\/plain":{"en":{"":"inception"}}},"{\"value\":{\"time\":\"+2006-08-07T00:00:00Z\",\"timezone\":0,\"before\":0,\"after\":0,\"precision\":11,\"calendarmodel\":\"http:\\\/\\\/www.wikidata.org\\\/entity\\\/Q1985727\"},\"type\":\"time\"}":{"text\/html":{"en":{"P571":"7 August 2006"}},"text\/plain":{"en":{"P571":"7 August 2006"}}}}": -->
38:
278:
253:
82:
168:
the pendulum stays constant with temperature. Zinc-steel gridirons like this example only required 5 rods, while brass-steel gridirons required 9 rods due to the smaller difference between the thermal expansion of brass and steel. It is a "seconds pendulum", with a period of 2 sec so each swing took one second, with a length from suspension to bob center of approximately one meter (39 inches).
155:, was a temperature-compensated pendulum that stayed the same length with changes in temperature, preventing the variations in timekeeping that occurred with ordinary pendulums when their pendulum rods expanded or contracted with changes in temperature. In the gridiron the pendulum bob is supported by a "grid" of rods of two different metals, in this case steel
396:
476:
167:
so that expansion of the steel rods makes the pendulum longer, while expansion of the brass rods pushes the bob up, making the pendulum shorter. By making the rods of the correct length, the greater expansion of the zinc compensates for the greater length of the steel rods, and the overall length of
288: Note that a few countries have copyright terms longer than 70 years: Mexico has 100 years, Jamaica has 95 years, Colombia has 80 years, and Guatemala and Samoa have 75 years. This image may
283:
397:
493:== Summary == {{Information |Description={{da|"Tidens naturlære" 1903 af Poul la Cour, Fig. 22. Kompensationspendulet. Bogen findes digitalt på
527:{{Information |Description="Tidens naturlære" 1903 af Poul la Cour, Fig. 22. Kompensationspendulet.<br> Bogen findes digitalt på
151:
from a precision regulator clock, in the book "Tidens naturlære" (Nature of time) 1903 by Poul la Cour. The gridiron pendulum, invented 1726 by
42:
48:
309:
209:
93:
332:
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.
61:
266:
509:
504:
531:<br><br> "Tidens naturlære" (Nature of time) 1903 by Poul la Cour, Ill. 22. Temperatur compensate
407:
386:
593:
304:
implement the rule of the shorter term. Copyright may extend on works created by French who died for France in
313:
187:
From the book "Tidens naturlære" (Nature of Time) 1903 by Poul la Cour, fig. 22. The book is digitized at
297:
541:
The following pages on the
English Knowledge use this file (pages on other projects are not listed):
528:
494:
188:
137:
317:
136:"Tidens naturlære" 1903 af Poul la Cour, Fig. 22. Kompensationspendulet. Bogen findes digitalt på
475:
470:
101:
52:
37:
331:
8:
321:
497:}}<br> {{en|Temperature compensated [[Knowledge:gridiron pendulum|gridiron pendulu
148:
545:
88:
376:
261:
152:
583:
555:
486:
198:
520:
305:
417:
286:
to indicate why this work is in the public domain in the United States.
550:
443:
Click on a date/time to view the file as it appeared at that time.
573:
265:
in its country of origin and other countries and areas where the
316:(known as the Great Patriotic War in Russia) and posthumously
292:
be in the public domain in these countries, which moreover do
603:
300:. Honduras has a general copyright term of 75 years, but it
177:
76:
370:
Add a one-line explanation of what this file represents
539:
564:
441:
100:
Commons is a freely licensed media file repository.
66:(564 × 1,856 pixels, file size: 261 KB, MIME type:
340:https://creativecommons.org/publicdomain/mark/1.0/
81:
204:
173:
123:
194:
183:
14:
566:The following other wikis use this file:
346:Creative Commons Public Domain Mark 1.0
252:
163:. The rods are connected by a frame
112:
247:
434:
13:
375:
369:
142:
130:
113:
59:
617:
374:
314:the Eastern Front of World War II
540:
360:
276:
251:
80:
31:
21:
357:
320:victims of Soviet repressions (
284:United States public domain tag
143:
561:
438:
356:
131:
26:
1:
584:Tidens naturlære/Penduluhret
536:
382:Items portrayed in this file
223:
7:
580:Usage on da.wikisource.org
271:life plus 70 years or fewer
10:
622:
600:Usage on vi.wikipedia.org
590:Usage on fa.wikipedia.org
570:Usage on cs.wikipedia.org
312:), Russians who served in
126:Tidens naturlære fig22.png
120:
115:
435:
330:
250:
16:
359:
298:rule of the shorter term
282:You must also include a
87:This is a file from the
36:
526:
492:
176:
91:. Information from its
471:03:34, 27 January 2009
157:(dark rods, R & S)
94:description page there
41:Size of this preview:
529:s:da:Tidens Naturlære
495:s:da:Tidens Naturlære
189:s:da:Tidens Naturlære
138:s:da:Tidens Naturlære
505:16:22, 7 August 2006
259:This work is in the
47:Other resolutions:
53:564 × 1,856 pixels
562:Global file usage
546:Gridiron pendulum
534:
368:
337:
336:
326:
246:
245:
220:
219:
213:
210:Reusing this file
149:Gridiron pendulum
109:
108:
89:Wikimedia Commons
32:Global file usage
613:
574:Kyvadlové hodiny
517:
483:
445:
366:
353:
350:
347:
344:
341:
322:more information
310:more information
281:
280:
279:
269:is the author's
255:
254:
248:
242:
239:
236:
233:
228:
227:
207:
179:
147:
135:
127:
121:
105:
84:
83:
77:
71:
69:
56:
43:182 × 599 pixels
621:
620:
616:
615:
614:
612:
611:
610:
560:
542:
535:
523:
515:
489:
481:
437:
436:
433:
432:
431:
430:
429:
428:
427:
426:
424:
414:
413:
412:
410:
395:
394:
393:
392:
391:
389:
373:
372:
371:
351:
348:
345:
342:
339:
325:
277:
240:
237:
234:
231:
226:
221:
199:Morten Bisgaard
169:
161:(light rods, T)
140:
125:
118:
111:
110:
99:
98:
97:is shown below.
73:
67:
65:
58:
57:
49:73 × 240 pixels
46:
12:
11:
5:
619:
609:
608:
607:
606:
598:
597:
596:
588:
587:
586:
578:
577:
576:
563:
559:
558:
556:Pendulum clock
553:
548:
538:
533:
532:
525:
521:
518:
514:1,500 × 1,856
512:
507:
502:
499:
498:
491:
487:
484:
478:
473:
468:
464:
463:
460:
457:
454:
451:
448:
440:
425:
422:
420:
419:
418:
416:
415:
411:
406:
404:
403:
402:
401:
399:
390:
385:
383:
380:
379:
378:
377:
365:
364:
361:
358:
335:
334:
328:
327:
296:implement the
287:
267:copyright term
256:
244:
243:
225:
222:
218:
217:
214:
202:
201:
196:
192:
191:
185:
181:
180:
175:
171:
170:
128:
119:
117:
114:
107:
106:
85:
75:
74:
40:
35:
34:
29:
24:
19:
9:
6:
4:
3:
2:
618:
605:
602:
601:
599:
595:
592:
591:
589:
585:
582:
581:
579:
575:
572:
571:
569:
568:
567:
557:
554:
552:
549:
547:
544:
543:
530:
524:
519:
513:
511:
508:
506:
503:
501:
500:
496:
490:
485:
479:
477:
474:
472:
469:
466:
465:
461:
458:
455:
452:
449:
447:
446:
444:
423:7 August 2006
421:
409:
405:
388:
384:
381:
362:
355:
354:
333:
329:
323:
319:
318:rehabilitated
315:
311:
307:
303:
299:
295:
291:
285:
275:
274:
272:
268:
264:
263:
262:public domain
257:
249:
235:Public domain
232:Public domain
230:
229:
215:
211:
206:
203:
200:
197:
193:
190:
186:
182:
178:7 August 2006
172:
166:
162:
158:
154:
153:John Harrison
150:
146:
141:
139:
134:
129:
122:
103:
96:
95:
90:
86:
79:
78:
72:
63:
62:Original file
54:
50:
44:
39:
33:
30:
28:
25:
23:
20:
18:
15:
594:آونگ شبکهای
565:
480:564 × 1,856
442:
439:File history
338:
306:World War II
301:
293:
289:
270:
260:
258:
164:
160:
156:
144:
132:
102:You can help
92:
60:
22:File history
124:Description
537:File usage
456:Dimensions
205:Permission
27:File usage
488:Chetvorno
453:Thumbnail
450:Date/Time
408:inception
398:inception
224:Licensing
165:(a,b,f,g)
159:and zinc
145:English:
68:image/png
551:Pendulum
522:Bisgaard
516:(277 KB)
482:(261 KB)
363:Captions
604:Con lắc
467:current
462:Comment
387:depicts
367:English
133:Dansk:
116:Summary
64:
216:PD-Old
195:Author
184:Source
352:false
349:false
241:false
238:false
459:User
302:does
174:Date
17:File
343:PDM
294:not
290:not
324:).
273:.
51:|
45:.
308:(
212:)
208:(
104:.
70:)
55:.
