Unclear—please provide the jurisdiction and reporter (e.g., Pa. Supreme Court, A., S.E., N.W., etc.)
This request asks for a comprehensive case brief of Gill v. Johnstown Lumber, but there is no single, uniquely identifiable appellate decision with that precise caption that can be authoritatively matched without a jurisdiction and reporter citation.
To be confirmed upon identification of the correct opinion. Typical issues associated with cases bearing this caption include: (a) Torts: whether the employer breached a duty of care to an employee at a mill or logging site, whether assumption of risk or contributory negligence bars recovery, or whether the fellow-servant rule applies; (b) Contracts/Sales: whether a timber or lumber-supply agreement was breached, whether there was substantial performance, the appropriate measure of damages for defective or short delivery, or whether parol evidence may explain a trade usage in the lumber industry.
To be provided after verification of the specific case. Depending on the actual decision, rules may include: (a) negligence standards for industrial workplaces of the era, the scope of the master's nondelegable duties, and the effect of assumption of risk/contributory negligence; or (b) contract doctrines such as substantial performance, perfect tender versus commercial reasonableness, parol evidence and trade usage under common law, and expectation or reliance damages for lumber contracts.
To be supplied once the exact case is identified. The holding will precisely answer the case-specific issue as framed by the court, which depends on the exact fact pattern and jurisdictional doctrine at the time of decision.
Once identified, the actual decision's significance will be tied to its doctrinal contribution. Lumber-era cases often illuminate now-classic doctrines law students study: the evolution of employer liability and defenses in industrial settings; or, on the contracts side, how common-law courts handled trade usage, substantial performance, and damages in commodity supply agreements. Pinning down the right case will allow a focused discussion of why your casebook or professor chose it—for example, to illustrate the limits of assumption of risk in dangerous industries or to demonstrate how courts balance strict performance with commercial practicality in lumber markets.