13 



of calculation, and a reference to our returns will show that we- 

 made only such a trifling addition at the beginning of 1886 as 

 our altered circumstances appeared to warrant. The second 

 change, in 1885, was more important. In that year, for the first 

 time within my knowledge, the emigration from South Australia 

 largely exceeded the immigration, and this continued to be the 

 case during the whole of the following year. In 1885 the excess 

 was 6,581. In 1886 it was 7,92^. These were the losses by sea. 

 "VYe have no means of knowing the increase or decrease of popu- 

 lation by land, but we shall probably be near the mark if we set 

 down 15,000 as the total loss of the colony during two years by 

 excess of emigration. As a matter of fact we did not suffer a 

 diminution of population, because the excess of births over deaths 

 during those years as nearly as possible balanced our loss. All 

 this was taken into account and dealt with in our estimates for 

 the whole colony ; but when we come to the estimation of local 

 populations, our difiiculties begin. In hard times there is a con- 

 stant migration of the people from one place to another. Men 

 travel to any part of the colony when there is a chance of obtain- 

 ing work, and the estimate of numbers in any one locality can 

 only be regarded as approximate. Until a new census be taken 

 it will be impossible to guarantee a strictly accurate return. 



Dr. Jamieson suggests a mode of estimating local population 

 which he thinks Avould be more reliable than that usually fol- 

 lowed. He proposes to make the number of births in a given 

 period the basis for calculation. His method of proceeding from 

 the known to the unknown is this — we know that in the census 

 year there was a certain population, say in Adelaide and suburbs ; 

 we know also that in the same year there was a certain number 

 of births. If we want to get an approximate estimate of the^ 

 population in any future year, we have only to take the births 

 during the year, and assuming there is a fixed relation between 

 the births and population, we can estimate from the births what 

 the population for that year ought to be. In other words, sup- 

 posing that in the census years it required 24 people to produce 

 one baby, we have only to multiply the births in any other year 

 l)y 24 and the product will give us a fair estimate of the popula- 

 tion. It will occur to you that the accuracy of the result must 

 depend so much on other factors that this mode of calculation 

 cannot be accepted as reliable. We want to know something 

 more about the 24 people. How many of them are children- 

 How many unmarried, and of those that are married how many 

 have the depressed times separated — the wife being left in charge 

 at home while the husband is far away working, or seeking work, 

 to suj^port his family. In a normal steady-going condition of 

 society Dr. Jamieson's method might give fairly accurate results. 



