4.1. Bhūparīkṣā (selection of the plot)

Before a plot is chosen for construction, the soil in the land must be tested for the construction of an ideal town, city, house or any architecture and the surroundings. In the case of towns or cities, an ideal town must have a green belt of forests with tall trees and plants full of flowers. This is necessary, not only from the point of view of healthy climate, but also from the perspective of growth and maintenance of the population requiring food, fuel and fodder.

Water is one of the mandatory things that people need. No life can subsist without a good natural supply of water and hence the rivers, lakes, ponds and tanks are indispensible pre-requisites for the laying out of a town. Therefore, practically all the towns, cities and temples have evolved near water bodies like rivers or lakes. The presence of water and trees presupposes a fertile soil condition.

The Vāstuśāstra texts are thus full of details about the geological survey of land. The different varieties of soils having different colours, smells and taste were categorised and their usage was also laid down by the texts. Therefore, a site is tested based on the above factors, by the trees grown nearby, by the presence of the underground spring, by birds and animals that frequent them and by the germination of seeds in the soil.

To categorise the soil, first the site is levelled and a pit is dug in the measure of 1:1 ratio. The soil taken from such digging is again filled into the pit. If there is soil remaining after filling the pit, then the land is considered to be perfect or uttama; if there is no soil remaining then it is categorised as madhyama and if there is no enough soil to fill the pit, it is considered as a poor site or adhama (Kāśypa Śilpaśāstra, I. 37-8):

hastātraṃ tataḥ khātvā khātvā tadbhūmimadhyame |
pūrite tu mṛdā khāte hyadhikā cottamāmahī ||
samā tu madhyamākhyātā hīnā sākanyasāmatā |
agratācchottamāmadhyā mārgahīnānyasadmani ||

The uttama bhūmi is fit for all types of constructions, the madhyama bhūmi is moderate for all and the adhama bhūmi must be avoided as it is not fit for any construction. Similarly four different colours of the soil are listed by the texts and their usages are also given. Only after considering all these, the best land is used for construction of temples,