Mercury In 4th house according to classical book of astrology
Phaldepika
When Mercury is placed in 4th house, native will be expert in calculations. He will be very intelligent and pleasent in speaking. He will has good friend, comfort, materialistic happiness, property and enjoying all sorts of happiness.
Jatak Parijat
When Mercury is placed in 4th house, native will be without happiness of friends and relatives. He has deep knowledge, he will be rich and scholar.
Saravali
When Mercury in 4th house, native will be rich. He will has support of public. He will be fortunate. He has good happiness of vehicles. He will be well dressed. He has very good friend circles and relatives. He will be scholar. He will be gain knowledge day by day.
Yavanjatakam
Native with Mercury in 4th house is indicating native may has good happiness by own self efforts. Native will be making own house by own self. No one is equal to him in works.
Vridh Yavanjatakam
When Mercury in 4th house, native will be very intelligent. He has multiple sorts of knowledge and skills. He has good physique. He may has profit from agriculture land. He may be polite in nature. He will be without of any disease. He will be destroyed his enemies.