New Soil$ Building 
                                              April 16, 1935 
 
 
 
Dr. A. D. Middleton 
 
 
Dear Dr. MKdletoni 
 
         Trzera.  two Amriom pubiation vorth metioning on the 
ques4ion of  ptiam tmeratu  r   tifiial Inbation of past ewe 
           Px m ff, Alex L.                                       °lA
M & u a gn o W B r s 
 
 
 
 
 
              C  e  A   c    r  3st Station, State Collae, 
              Pennsylania, Ocotber, 1933. 
 
         1 am writing both of the athors to sind you at oce a copy of 
their publiations. 
 
         The Cal01nba& per repreets a careful piece of wor bt to 
empirical in cacter, that is, he sipy fbvd, somethin       icho would work.

 
         The 2uioff paper begins *er     Callebad left off ad overs 
the results of a sies of trials in which a good a     egs       deliber-

ately spoiled, aM hene the itstgation ca       really be said to have fb=

something *ih could be aolled oti  . 4a    f advie a t      at  of 
1007. for the first 8 dy, 101'7. for the soiond 9 days, A     1007, for 
Ue ooanuding perio of the icubatio. These figrs apply to 
draft electric inuobators (ventilation constant. relative tnuidity 62.5%.

 
         bwanoff foun that the lowerin of the temrure     uring the 
final period had a beneficial effect. 
 
         His tierature rmings ere taken at a heigt above the 
pheas~t eggs equal to the diamter of a hen's egg. 
 
         Famanff also got good results from a contant temprature with 
a bouid.ity gradally lowering from 7% daing~ the first 6-day period., 7Q%

the seond 9-da per.od, and 6%    for the c   11dig period.. Jet "hat
the 
oonnection ws betwoen this aM the preeding method is ot clear to m. 
 
         I have n perso      knoaledge *hatver on this subje.t, and hwao

you =q find the above Interpretation of the literature somewat faulty. 
 
 
Yours sincerely.