Imagens das páginas
PDF
[merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][ocr errors]

It is a cruel mortification in searching for what is instructive in the history of past times, to
find that the exploits of conquerors who have desolated the earth, and the freaks of tyrants who have
rendered nations unhappy, are recorded with minute and often disgusting accuracy — while the
discovery of useful arts and the progress of the most beneficial branches of commerce are passed
over in silence, and suffered to sink into oblivion.
rto be Rtsox.

[merged small][ocr errors]
[ocr errors][merged small][ocr errors][graphic][graphic][graphic][graphic][graphic][graphic][graphic][graphic][graphic]
[ocr errors]

CIRCUMSTANCEs having led me, in early life, to take an interest in practical hydraulics, I became anxious to obtain an account of all the contrivances employed by different people to raise water—whether for domestic, agricultural, mining, manufacturing, or other purposes; and great was the disappointment I felt on learning that no book containing the information I sought had ever been published. This was the case between thirty and forty years ago; and, notwithstanding the numerous journals and other works devoted to the useful arts, it is in a great measure the case still. No one publication, so far as my knowledge extends, has ever been devoted to the great variety of devices which the human intellect has developed for raising liquids. That such a work is wanted by a large class of mechanics, if not by others, can hardly be questioned; and it is somewhat surprising that it was never undertaken.

It appears from La Hire's Preface to Mariotte's Treatise on the Motion of Fluids, that the latter philosopher often expressed a determination to write “on the different pumps and other engines which are in use, or which have been proposed,” but unfortunately he did not live to carry his design into effect. The celebrated work of Belidor, from its extent, and the variety of subjects embraced and illustrated, stands at the head of modern works on hydraulic devices; but of the four large volumes, a small part only is devoted to machines for raising water, and many such are not noticed at all : besides, the cost of the work and the language in which it is written will always prevent it from becoming a popular one with American or English machinists.

Having in the course of several years collected memoranda and procured most of the works quoted in the following pages, I have attempted to prepare a popular volume on the subject—something like the one I formerly longed for—feeling persuaded that it will be as acceptable to mechanics under circumstances similar to those to which I have alluded as it would then have been to myself. Every individual device for raising water has, of course, not been described, for that would have been impossible; but every class or species will be found noticed, with such examples of each as will enable the general reader to comprehend the principle and action of all. In addition to which, inventors of hydraulic machines can here see what has been accomplished, and thus avoid wasting their energies on things previously known.

« AnteriorContinuar »