From 1680 to 1850 is a long period of time for a particular style of timepiece to run without interruption or without displacement by any other fashion. It may naturally be supposed that during this period changes have occurred in form, in decoration, and in a score of minor details delightful to the collector and interesting to the student of form in design. The inception of the long case was due to the common use of the seconds pendulum. This required a certain space to swing in, and the pendulum was of a certain length. This undue length does not seem to have been necessary in the wall clock of the so-called "Act of Parliament" type, and as Lord Grimthorpe, the constructor of "Big Ben" at Westminster, says: "Spring clocks are generally resorted to for the purpose of saving length; for as clocks are generally made in England, it is impossible to make a weight clock capable of going a week, without either a case nearly 4 feet high, or else the weights so heavy as to produce a great friction on the arbour of the great wheel. But this arises from nothing but the heaviness of the wheels and the badness of the pinions used in most English clocks, as is amply proved by the fact that the American and Austrian clocks go a week with smaller weights and much less fall than English ones, and the American ones with no assistance from fine workmanship for the purpose of diminishing friction, as they are remarkable for their want of what is called 'finish' in the machinery, on which so much time and money is wasted in English clock-work." =Its Dutch Origin.=--As we have before explained, the marquetry case came straight from Holland. Our "grandfather" was a Dutchman, as far as clock-cases go. The Dutchman Huygens is credited with having been the first to employ the pendulum in the mechanism of the clock. Leonardo da Vinci, that stupendous genius, left notes as to his study of the pendulum (1452-1520), and Galileo came with his later studies (1564-1642). It is a disputed point as to when and where the pendulum came into being. We must accept Huygens (1629-95) as the practical exponent of the pendulum, although not the original discoverer of its properties. But at any rate, the long-case clock may be generally accepted as coincident with the use of the long or seconds pendulum. And to Holland we must look for this habitual usage of the long wooden case to protect the weights and the pendulum. Among the designs of Marot there are drawings of long-case clocks certainly more ornate than those usually associated with such an early period (this was about 1660 to 1680), and French Louis XIV and Louis XV tall clocks are built on these lines, and Chippendale at a later period found Marot an exceedingly prolific master of design to study.