Directions: Arrange the sentences A, B, C and D to form a logical sequence between sentences 1 and 6.

1. The modern era may be said to have begun about the year 1895. A. So great a revolution in scientific thought has not occurred since Copernicus showed that the earth went round the sun. B. The first step was the experimental demonstration that there exist little electrified bodies very much smaller than a hydrogen atom. C. Between that year and the year 1900, those researches were begun which have changed our whole conception of matter. D. Further, these studies have changed our whole idea of the meaning and purpose of physical science.
2. These little bodies were produced by passing an electric current through a glass tube almost entirely exhausted of air.