In every department of human affairs,Practice long precedes Science systematic enquiry into the modes of action of the powers of nature,is the tardy product of a long course of efforts to use those powers for practical ends.

• 在人类活动的每一个领域，实践都长期领先于科学。对自然力作用方式的系统研究，是长期努力将自然力应用于实际以后的产物。