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Memoirs of the Royal Astronomical Society Volume 22 by Royal Astronomical Society - Paperback
105.00 درهم

Memoirs of the Royal Astronomical Society Volume 22 by Royal Astronomical Society - Paperback

كن أول من يقيِّم هذا المنتج 

105.00 درهم 

  - ستوفر -105.00 درهم
الأسعار تشمل ضريبة القيمة المضافة  التفاصيل
رقم ال ISBN
9781130504279
الفئات
تاريخ
الكاتب
Royal Astronomical Society
الناشر
Rarebooksclub.com
الوصف:

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1854 Excerpt: ...quite inconsiderable, especially when we remember that many of the causes of variations in the force of the pallet-wheel recur at regular periods and at short intervals, so that they ...

تشحن من الولايات المتحدة
اشحن الى دبي (تغيير المدينة)
التوصيل خلال الثلاثاء ٤ ديسمبر - الخميس ٦ ديسمبر الي دبي

حالة السلعة:
جديدة
البائع:
InternationalBookStore (85% تقييم ايجابي)

معلومات المنتج

  •  

    المواصفات

    رقم ال ISBN
    9781130504279
    الفئات
    تاريخ
    اللغات
    الانجليزية
    الرقم المميز للسلعة
    2724353287212
    المؤلفين
    الكاتب
    Royal Astronomical Society
    رقم ال ISBN
    9781130504279
    الفئات
    تاريخ
    اللغات
    الانجليزية
    الرقم المميز للسلعة
    2724353287212
    المؤلفين
    الكاتب
    Royal Astronomical Society
    المؤلفين
    الناشر
    Rarebooksclub.com
    معلومات تقنية
    غلاف الكتاب
    غلاف عادي
    اللغات والبلدان
    لغة الكتاب
    الانجليزية
    إقرأ المزيد
  •  

    الوصف:

    This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1854 Excerpt: ...quite inconsiderable, especially when we remember that many of the causes of variations in

    This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1854 Excerpt: ...quite inconsiderable, especially when we remember that many of the causes of variations in the force of the pallet-wheel recur at regular periods and at short intervals, so that they produce no perceptible irregularity in the rate of the clock. If the above were really the principal defect of this escapement, we might be satisfied with making such improvements in the train as it admits of; but that in my opinion is not the true state of the case. When we compare the pendulum of an astronomical clock, which frequently weighs upwards of 15 lbs., with the balance of a marine chronometer, we should scarcely suspect that the force which is employed to keep the clock going is only about half of that employed for the chronometer. Such, however, is, I believe, the fact, if not in general, at least in many instances which cannot be regarded as extreme. Nevertheless, the power employed for the clock is commonly three or four times greater than what would be required, if the whole of it were applied to maintain the oscillation of the pendulum without loss by friction or other causes. Hence it appears what a delicate piece of mechanism the escapement of an astronomical clock might be, compared to what it usually is; and it is not surprising that Royal Astron. Soc. Vol. XXIJ. T friction, the thickening of the oil on the pallets, and the other mechanical imperfections of the escapement, should materially influence the pendulum. It is often assumed that the friction on the circular part of the pallet is small in amount and unimportant in its nature. With respect to its amount, I believe it is often not far short of equal to all the retarding forces which act on the pendulum independent of the escapement; and with respect to its being unimportant, this assumption is founde.

    خصائص المنتج:
    • الفئات: تاريخ
    • غلاف الكتاب: غلاف عادي
    • لغة الكتاب: الانجليزية
    • الكاتب: Royal Astronomical Society
    • الناشر: Rarebooksclub.com
    • رقم ال ISBN: 9781130504279
    • عدد الصفحات: 88
    • لأبعاد (الارتفاع*العرض*العمق): 9.69 x 7.44 x 0.18 inches
 

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