6i4 



THE POPULAR SCIENCE MONTHLY. 



the species found lower down in the canons 

 often show a greater affinity to Mexican and 

 Californian types. I was more fortunate 

 than Lieutenant Carpenter, and took over 

 twenty species of butterflies above the tim- 

 ber-line. 



I have endeavored to show that some- 

 times at least insects are quite plentiful in 

 the Colorado mountains. They are cer- 

 tainly more plentiful in the mountain-re- 

 gions than on the plains. 



Yours very truly, 



J. Duncan Putnam. 

 Davenport, Iowa, January 10, 1ST7. 



EFFECTS OF THE WAR ON THE INCREASE 

 OF POPULATION IN THE LAST DECADE. 



To the Editor of the Popular Science Monthly. 



The Superintendent of the Ninth Cen- 

 sus, while showing the causes of loss in 

 population produced by the late war, neg- 

 lected to point out the actual decrease inci- 

 dent to this cause, as shown by the State 

 censuses of 1SG5. 



The retarding influence may be seen by 

 reference to the States of New York and 

 Massachusetts. 



In the former State, whereas the regular 

 increase for each period of five years had 

 been nearly 500,000, from 1860 to 1865 

 there was a decrease of 29,000. From 1865 

 to 1870 there was an increase of 529,000. 

 (" Manual " for 1870.) 



In Massachusetts the increase of popu- 

 lation from 1850 to 1855 was 138,000; 

 from 1855 to 1860 it was 90,000; from 

 1860 to 1865, 36,000; from 1865 to 1870, 

 190,000; and from 1870 to 1875, 194,000. 

 The regularity of increase in the State is 

 shown bythe fact that the difference be- 

 tween the actual population in 1870 and 

 that computed on the supposition that the 

 increase was in arithmetical progression 

 was only 2,120. ("Massachusetts State 

 Census " for 1875, vol. i., p. xxxii.) 



Ii\ these two States, therefore, the in- 

 crease of population during the war-period 

 was only 7,000, while in the next five-year 



period it was fully a hundred times as 

 great. The population of these two States 

 was over 6,000,000, or more than fifteen 

 per cent, of the total population of the 

 United States. 



As it may be urged that these States 

 suffered heavily in loss of immigration, we 

 will attempt to estimate their actual loss in 

 this respect. The total loss of immigration 

 is estimated (" Ninth Census," vol. i., p. 

 xix.) at 350,000. If we suppose the immi- 

 gration into a State to be proportionate to 

 the foreign population of that State, the 

 proportion of loss in immigration for these 

 two States will be 27 per cent, of the whole 

 loss, or about 94,500. Omitting the loss in 

 immigration, therefore, the total gain of 

 these two States will be 101,500. Even if 

 we further suppose that these States suf- 

 fered another special loss of 48,500, the 

 total gain would still be only 150,000. 

 Multiplying this by 8, the ratio between the 

 increase of population in these States (700,- 

 000) from 1865 to 1870, and the estimated 

 increase of the United States for the same 

 time, we get for the total gain of the coun- 

 try, without considering the loss in immi- 

 gration, 1,200,000. Deducting this loss, we 

 have for the entire gain 850,000. 



We have no reason to suppose that- 

 New York and Massachusetts were especial 

 sufferers during this period. Many of the 

 Southern States probably suffered more, es- 

 pecially in loss of negro population, which 

 amounted to half a million during this pe- 

 riod (" Ninth Census," vol. i., p. xviii.). 

 There is, then, no reason to suppose that 

 the above estimate falls far short of the 

 truth. Even if the estimate is increased to 

 1,500,000, which seems improbable, the 

 population of the country in 1865 would 

 still fall short of 33,000,000. This would 

 indicate for the succeeding period of five 

 years an increase of 5,500,000, which is 

 somewhat above the average. That this 

 large increase is actual is rendered proba- 

 ble by the corresponding large increase in 

 Massachusetts and New York for the same 

 time. 



Alexander Duane, Union College. 



