I will present some aspects of my new book Split and Splice (Chicago University Press 2023). The overall aim of the book is to give a consistent assessment of experimentation as a knowledge-generating procedure by focusing on its practice. In the first part of the book, the different facets of the process of experimentation are dealt with from a microscopic perspective. The second part deals with its macroscopic features. Taken together, they render visible what is usually overlooked with respect to experimentation, either because it remains below the threshold of perception or because it lies beyond it. Experimental systems are taken as a starting point. They are in themselves already complex units of epistemic objects and the apparatus used to investigate them. Different aspects of an experimental setup are examined more closely in the first part of the book: the production of traces and their conversion into data, the construction of models, the ways of making things visible, the forms of grafting new instruments and procedures onto an existing ensemble, and note-taking. These aspects will be juxtaposed and characterized in their peculiarities and interrelations. The second part of the book focuses on the interrelations that experimental systems entertain among themselves. The characteristic temporal, spatial, and narrative dimensions of these articulations will be traced. Concepts that serve as guidelines in the investigation, such as that of experimental culture, will be presented by way of examples, and they will be developed and tested for their usefulness on materials taken from the history of twentieth-century life sciences.