The Ridbaz’ attack on the Brisker method is well known. In the introduction to his responsa, Beit Ridbaz (Jerusalem, 1908), Ridbaz writes as follows:
A certain rabbi invented the “chemical” method of study. Those in the know now refer to it as “chemistry,” but many speak of it as “logic.” This proved to be of great harm to us for it is a foreign spirit from without that they have brought in to the Oral Torah. This is not the Torah delivered to us by Moses from the mouth of the Omnipresent. This method of study has spread among the yeshivah students who still hold a gemara in their hands. In no way does this type of Torah study bring men to purity. From the day this method spread abroad this kind of Torah has had no power to protect its students. . . . It is better to have no rosh yeshivah than to have one who studies with the “chemical” method.
In his ethical will, printed at the end of his responsa, Ridbaz returns to this criticism and directs his sons: “Be careful, and keep far away from the new method of study that has in recent years spread through Lithuania and Zamut. Those knowledgeable in Torah refer to it as ‘chemistry.'”
Here is the Hebrew text of the ethical will from HebrewBooks here:
מהלימוד החדש שיצא בשנים האחרונות בזאמוט וליטא אשר המביני תורה קוראים לה כמיאה הזהרו מאוד, והתרחקו ממנו.