What are the ethos,logos,and pathos of chapters 1-4 in Frederick Douglass, an American Slave

Ethos, pathos, and logos refer to three modes of persuasion, or persuasive appeals. They deal with the manner in which a speaker (or author) tries to draw their audience toward their point of view. 
Briefly, ethos appeals to the ethics, or moral standards, of the reader. This is when speakers suggest reasons why they can be trusted and relied upon.
Ex: That teacher has never had a student fail their final exams, and he always speaks kindly to students.
Pathos appeals to the listener's emotions, or feelings:
Ex: Don't be the only student who fails the exam; study, because you can pass the test!
Logos appeals to the logic of the listeners:
Ex: Over 50% of consumers agree that this new product is the most comfortable pillow in our modern world. 
Frederick Douglass began his speaking career as fugitive slave, meaning a slave who had run away to the north. His mother was a slave and his father was an unknown white man. He was raised by his grandparents and was estimated to be 23 years old when he began publicly speaking. (Many slaves and slave masters did not keep records of slaves' birth dates.) He explains in chapter one

"I have no accurate knowledge of my age, never having seen any authentic record containing it. "

He soon became a well-known speaker, as well as a prolific writer; he wrote three autobiographies, recounting major events of his life. His primary purpose in writing was to share his story, in the hopes of aiding the abolition movement. He wanted to show the horrors of slavery and to see it discontinued, or abolished, in the United States. 
One example of ethos in the text is seen in chapter two: 

"My master's son-in-law, Captain Auld, was master of the vessel; she was otherwise manned by the colonel's own slaves. Their names were Peter, Isaac, Rich, and Jake. These were esteemed very highly by the other slaves, and looked upon as the privileged ones of the plantation; for it was no small affair, in the eyes of the slaves, to be allowed to see Baltimore."

Here, readers learn about Douglass's life at his first master's house. First, we hear about his master's family. Then, we hear about the other slaves. For instance, we hear that there were several "esteemed" slaves, who were allowed to go with Captain Auld to Baltimore on business. This shows the trustworthy nature of these slaves and their loyalty to their master. They behaved both reliably and respectably. 
An example of pathos in the text is in chapter one:

"I never saw my mother, to know her as such, more than four or five times in my life; and each of these times was very short in duration, and at night. She was hired by a Mr. Stewart, who lived about twelve miles from my home. She made her journeys to see me in the night, travelling the whole distance on foot, after the performance of her day's work. She was a field hand, and a whipping is the penalty of not being in the field at sunrise, unless a slave has special permission from his or her master to the contrary—a permission which they seldom get, and one that gives to him that gives it the proud name of being a kind master. I do not recollect of ever seeing my mother by the light of day. She was with me in the night. She would lie down with me, and get me to sleep, but long before I waked she was gone. Very little communication ever took place between us. Death soon ended what little we could have while she lived, and with it her hardships and suffering. She died when I was about seven years old, on one of my master's farms, near Lee's Mill."

In this passage Douglass tells the sad story of his short-lived relationship with his mother. He explains that he rarely got to see his mother because she was a slave. He evokes pity from readers as he explains their separation, both physically and emotionally. 
Finally, an example of logos in the text is seen in chapter two:

"Here, too, the slaves of all the other farms received their monthly allowance of food, and their yearly clothing. The men and women slaves received, as their monthly allowance of food, eight pounds of pork, or its equivalent in fish, and one bushel of corn meal. Their yearly clothing consisted of two coarse linen shirts, one pair of linen trousers, like the shirts, one jacket, one pair of trousers for winter, made of coarse negro cloth, one pair of stockings, and one pair of shoes; the whole of which could not have cost more than seven dollars. The allowance of the slave children was given to their mothers, or the old women having the care of them. The children unable to work in the field had neither shoes, stockings, jackets, nor trousers, given to them; their clothing consisted of two coarse linen shirts per year. When these failed them, they went naked until the next allowance-day. Children from seven to ten years old, of both sexes, almost naked, might be seen at all seasons of the year."

In this paragraph, Douglass lists specific facts about the allowances the slaves received for clothing, food, and other necessities. Rather than telling an emotional story about how cold they were in the evenings without sufficient clothing, Douglass lists exactly what items slaves were given. He expects that readers will draw their own conclusions about whether the slaves' needs were met.
Ultimately, Douglass employs ethos, pathos, and logos to compile his life story and persuade others of the evils of slavery.