On the following link, we can have on essay more material than we can read in a year or two.
http://www.readbookonline.net/essays/
Saadat Ali Shah of "Exploring the World of English" recommends that the readers should start with essays of Joseph Addison (I personally found him very pleasing to the ear.), followed by Oliver Goldsmith and others.
Joseph Addison daily published a magazine "The Spectator" with Richard Steele in the 1710s. This was the influence on Sir Syed Ahmed Khan when he issued Tehzeebul Akhlaq. There are around 450 short essays on various topics. Reading them provides method in writting, style in expression and ease of clarity.