I've fixed up your first source analysis. Tell if it is OK or not in your view.
Source 2
Source 2 is a secondary source, taken from the secondary high school Modern History book Evidence of War. It shows the layout of a trench, a ubiquitous feature of World War I, by illustration. The illustration is a visual representation of the trench system, used in the place of descriptions or photographs, probably because of the author’s intention to provide better clarity and understanding for the reader, as the previous methods mentioned before might have been difficult for the target audience of the book (high school secondary students) to comprehend.
The author of this source is Anne McCallum, a secondary school teacher/ author who has the role of teaching secondary students about World War I. She wasn’t alive during World War I so this source isn’t a primary source but instead a secondary source. It is highly likely that she has gathered both primary and secondary sources in her research which may have influenced her perspective towards World War I and her own visual representation of a World War One trench system/ layout. This could potentially create potential bias which could have been manifested in her illustration. Depending on the types of sources she herself referred to during her research and her method of research this here could impede on the reliability of this source.
The source, being published in Evidence of War has the purpose to educate secondary school students undertaking study in Modern History. Through this, the target audience and the purpose or motive of her illustration could be established. It can be said that the target audience are secondary school students undertaking the study of World War I, so therefore the motive or purpose of this source is to educate and inform these students about the trench system of World War I.
The reliability and usefulness of this source may be questioned. The illustration was produced after more than 80 years since the end of World War One. This raises the question if this illustration is really analogous to the real trench system found in World War 1. However, this source correlates to other photographic and descriptive sources of the period. This reliability can be further supported as the source is very general (due to its motive), and no specifics are offered between German and Allied trench systems (which were noticeably different). Basically, it is a very fundamental display of the main features of the trench system which can be noted from such features of the illustration such as the barbed wire and the dugouts which the soldiers would sleep and rest in despite the uncomfortable conditions (known through the diaries and memoirs of soldiers who served in World War One)
In understanding all this, this source can be said to be reliable and/or not reliable in certain aspects. It is derived from many secondary sources, which with recent understandings and discoveries provide fairly accurate renditions on trench system. However, it may not be reliable if the potential bias of the author is taken into account which includes her perspective towards trench warfare and the research conducted towards it.
Conclusively, the source is useful to the historian for the reason that it provides generalised idea of the conditions experienced in World War I along with the foundation to understand why the soldiers had problems such as disease, mud and general discomfort. On the other hand it should be noted that the source has a purpose of educating secondary school students and does not include enough meticulous detail required to make judgments on the trench system of World War One.