Alauddin Khalji was the first to introduce the system of measurement for the assessment of revenue, using the produce of a biswas as the unit for calculating total revenue.

Introduction:
Alauddin Khalji was the ruler who introduced the system of measurement for the assessment of revenue using the produce of a biswas as the unit. This system was a significant administrative reform that aimed to enhance revenue collection and ensure fairness in taxation.

Explanation:
Background:
During Alauddin Khalji's reign, the Delhi Sultanate faced several challenges, including the threat of Mongol invasions and the need to strengthen the financial resources of the state. Alauddin Khalji implemented various reforms to stabilize the empire and consolidate his power.

Introduction of Measurement System:
Alauddin Khalji introduced a new system of measurement for revenue assessment, known as the "Dagh" system. Under this system, the revenue was assessed based on the produce of a unit of land called a "biswas." The biswas was an area of land that could be cultivated by a single plow.

Measurement of Produce:
The produce of the biswas was measured and recorded in terms of grains. The assessment was made based on the average yield of crops such as wheat, barley, and pulses. The measurement of the produce allowed the revenue officials to calculate the revenue to be collected from each unit of land accurately.

Standardization of Assessment:
The introduction of the measurement system standardized the assessment of revenue across the empire. Previously, revenue collection was often arbitrary, leading to corruption and unfair taxation. The new system ensured that the revenue collection was based on a scientific and standardized method.

Benefits:
The measurement system had several benefits. It allowed the state to estimate the agricultural productivity of each region accurately. It also enabled the government to plan for the allocation of resources and make informed decisions regarding taxation and revenue collection.

Impact:
Alauddin Khalji's introduction of the measurement system had a significant impact on revenue collection and administration. It increased the efficiency of revenue collection and reduced corruption. The system also provided a reliable source of revenue for the state, which allowed Alauddin Khalji to undertake various military campaigns and strengthen the empire.

Conclusion:
Alauddin Khalji's introduction of the measurement system for revenue assessment using the produce of a biswas as the unit was a crucial administrative reform. It standardized revenue collection, enhanced efficiency, and ensured fairness in taxation. This reform played a significant role in the stability and consolidation of the Delhi Sultanate during Alauddin Khalji's reign.