RESEARCH ACCOUNT

CURRENT SCIENCE, VOL. 97, NO. 1, 10 JULY 2009 42 e-mail: bala@iitk.ac.in

New insights on the modular planning of the Taj Mahal

R. Balasubramaniam

Department of Materials a nd Metallurgical Engineering, Indian Institute of Technology, Kanpur 208 016, India

Dimensional analysis has revealed that the modular planning of the Taj Mahal complex was executed using the traditional measurement units mentioned in the

A r th a sa st r a

, and,

in particular, the

vitasti

measuring 12

angulams

of 1.763 cm. The riverfront terrace and garden sections of the complex were planned using square grids of 90

vitasti

to the side, while the forecourt and caravanserai section using square grids of 60

vitasti

to the side. The logical numbers that result for the dimensions have been analysed to show the ease of division of these numbers into symmetric elements to understand quadratic division of space of the garden area and the triadic division of space of the mausoleum, including decimal divisions. A novel approach to understand the metrology of historical architectural structures of the Indian subcontinent is revealed. Keywords:

Arth asast ra

, architecture, measurement, metro- logy, Taj Mahal. T

HE

Taj Mahal complex is one of the most visited and well-known archaeological structures of India. This is also one of the wonders of the modern world

1

. The overall plan of the Taj Mahal complex (Figure 1) reveals that it was planned based on ordering of grids, with the main architectural features of the complex placed on bilateral mirror symmetry along the north–south axis. The four major sections of the complex, as they are referred to in Figure 1, are (

T

) the riverfront terrace which contains the Taj Mahal mausoleum (

M

), (

C

) the

charbag

(literally ‘four gardens’) in front of the riverfront terrace, (

J

) the

jilau khana

(literally ‘in front of the house’) which contains the gate (

G

), and finally, the caravanserai (

S

). The first detailed scholastic examination of the modu- lar planning of the complex was undertaken only in 1989, when Begley and Desai

2

analysed the measurements of different parts of the complex listed by Lahori

3

. Lahori was the official historian of Shah Jahan (

AD

1628–56), who commissioned the construction of the Taj complex. Lahori stated the measures in terms of the

gaz

and

zira

, which were Mughal linear measures

4,5

. One notices that the entire description of the dimensions of the complex by L ahori

3

is in terms of mainly illogical

gaz

figures. The appearance of illogical numbers in the design of the Taj complex and the Taj Mahal has been ignored so far and simply considered as being part of geometric under- standing

2,6

. Begley and Desai

2

proposed a simple fixed grid of 400

gaz

and its sub-divisions to describe the com- plex, but their analysis has been sho wn to be imprecise an d incorrect

6

. Recently, Barraud

7

recorded the most detailed dimen- sions of the complex and proposed a generated grid sys- tem to explain the modular layout of the complex

6

. Barraud utilized the traditional Mughal linear measure,

gaz

, assuming a conversion of 80.5 cm to a

gaz

. He con- cluded that the complex was planned as a tripartite rec- tangle composed of three 374-

gaz

squares

6

. Barraud propose d that the planni ng of the riverfron t terrace and the

charbag

sections can be understood in terms of square grids of 23

gaz

to the side, while that of the

jilauk hana

and caravanserai sections in terms of square grids of 17

gaz

to the side. Further, he noted that the transition from the 23-

gaz

grid pattern to the 17-

gaz

grid pattern occurred at the main gate (marked as

G

in Figure 1). The apparent illogicality in the numbers 23 and 17 of the sides of the grid patterns proposed by him is immediately striking, when the grid sides are expressed in terms of

gaz

. Barraud

6

has ignored the appearance of illogical numbers and the discrepancies in the measurement (which are primary evidence) as being due to errors in the contemporary descriptions, rounding-off errors, inaccuracies of reporting from third persons and errors in workmanship. These arguments are not convincing since the planning of the complex is precise and the quality of workmanship is par excellence. The modular planning of the complex can be viewed afresh from a totally different angle, by considering the use of a different system of measurement. Recent studies

8–10

have revealed that the measurement units described in Kautilya’s

Arthasa stra

11,12

, dated to around 300

BC

, can be us ed to underst and the e nginee ring plans of mos t eng i- neered structures of the Indian subcontinent through the ages, till the adoption of British units in early 20th cen- tury. In particular, these studies confirm the use of a con- stant basic measurement unit (the

angulam

) of 1.763 cm. Interestingly, this unit was derived, without any a priori assumptions, from plans of Harappan civilization settle- ment sites

13,14

. A similar unit also appears in the Lothal ivory

15

and Kalibangan terracotta

16