The Evolution of Hollerith's System

Around the time of the census Hollerith's machine evolved through many stages. One of the most practical developments was Hollerith's design to broaden the counting abilities of the machines. Each tabulator was equipped with 40 counters, but 235 separate points of information were to be tabulated. In addition the Bureau desired to count combinations of these points, for example, the number of widowed women or 18 year old men. Hollerith solved each of these problems.

In order to further increase the number of categories that the machines could count, each card would complete seven runs. To speed the process Hollerith attached a sorting box to the card reader. The box was divided into a number of compartments. To sort the cards, the lid of the corresponding compartment opened when a card with a certain characteristic, for example female, passed through the reader. The sorting readied the cards for subsequent runs that would be necessary to obtain additional information. Secondly, Hollerith devised a system of electric relays which allowed combinations of multiple points of inquiry to be counted.²

Hollerith's ingtegrating machine

The Census could determine every possible combination with little extra effort. Robert Porter, who headed the census, reported, "With these machines, the most complicated tables could be reproduced at no more expense than the most simple ones.²" This capability was not only important in determining information regarding the current population, but was also important in determining the impact of previous programs and in evaluting possible public policy changes. For example, the government paid $35 million in military pension². With Hollerith's machine, it was now possible to know how many veterns receiving government pensions war were "at each age period.²" Therefore they could estimate how long they would have to pay individuals. This would be important in setting budgets and expenditure plans, especially in the 1930 with the introduction of Social Security.²