Deosnaber 18, 1924*

w aear Dr. Flexam:-

     As a result of our conferenoe last %turdq? I thou&t that 1 would
aend you 821 outline  of npr general plan of work for next year.

    V;e hme found that tioae-rmarrow oan be depleted in the pigeon, rabbit
aad rdt b procredurss different from e#h s~ecles ad In sxmh a :vq Wit the rmrros
ean be readily brought back to normal.  fn folltiag the regeneration it appeara
that red blood-cmlls oom bauk 1x1 an entirely different IBLUUW from the white ueU@-

1.     lpls red blood-cells regpmerate withla collapeed caplllarlea in mm ia
wWsh the slmuailss wh5ch oarry blood are mirkedly 8oastricted, iadioatin.; soam of
lou orygen ten01 on.  This c;orrelstes with obaervatloaa made in high altitudes.
IQum 1 is from a plgwods rsarrow with a vasoular iaeotioa with ink aad ahow very
few patent eimaes but may ooll~~psed oapfllaries In whlah reds are beginalag to
form. There are ma white blood-treUs In this arm,  Correlb ted wl th this aondltlon
of the marrow, the fat hm disappmred aad its pIme has been taken by a gelatinaas
snbstaaoe*  Gelatinom a9arrow haa often been noted by pathologists. i;ie correlate
llm appearance with a ooadltioa in whicrh red cells are begiaaiag to form Beace
we thfak that the fWmatfoa of red blood-cells is aorr&&ed with ICW oxygen tension
plus :i gelatinous aabstame In the narrow*  Oar plan is to gx& the help of a Uhmiat
to extsact t&t? eubstaaee arhl@h makes the FZSUTQ;1 gelatiaotaa.  31 ;vlll faraish the
latinous state.  f do not kaow ?mw maeh of the gelatinous ernbstaaue a ohmiet
would need so q~ est&mtes of snimls for next year night vary within some what
wide Umits.

2.     F&are 2 shows the uonditioa of the mrmw when white blood mall8 are
fotiag* The vetpeels are prwrtiartlly all wide open siauses, filled :-llth oimalatiag
blood.  Se thiak that this mans that mbsrtxzes for the white cells are brought
la the blood stmxm  This eorrelzites with the fact that :i*:e got suuh a mmked
rnatwation of the welobllasts after trsasi%siaas Ila the case of lenoemia we reported
in the Deember amber of the Jouraal of Experimental I%dicine. Also, Carrel's
gmth produciag eubstmms la .leneocytes ) aad the showers of dead lemocytea In
the ~inxalctiag blood of whioh I &owed yoti the charts of S;bturda,y, all ladleate
that we q find spsoiflo ehemicral mbataaees frm the wtite blood-oells them
selves to experiment with oa We origin of the Vdhlte cells.  This phase of the
mbjec t then also seeds help form pi chemist.  Ia this work m should m.nt to
follow tmnsfmfoas m&e in the hospital with vital studies on the blood-aellri
;ilso we should want to fo1io.w the blood of patients aad animals getting radium or
X-raya.  &at it seems to ,ns that the ihndamental attauk must now be tb find the
chemical substances that iafluenere the formation of red ue11e MS distiartt iron the
white uella.  For the depletion of the mbbit *s marrow we need iazotivated cultures
of bmllll, thus we need heir fmnr the baoterlologioal side. Dr. Doaa, however,
Is fully aoqpetent to carry that end of the work,


Deaslnber 18, 1924.

    Dr. Ibaa in aomlng h&r% "Zondeg; and his letter eounds to me hopaft&
H am very keen to get hh  I think that he mrlg have gotten started on a quite
brilliant line of work all hfs own on t&e leacroeytea r&&oh he could also ear-
on with US4 I feel that he would be a very great adaitioa to our @map, bat I:
do not thin% that 3~. Peabody ~43.1 be verge willfag to let him go*  li know that
his salary this year is      and all his living expenses rfnce he livea at
the Boston City Bosppital.

    I spoke tow to one of onr ioorth year men, a G?r. A. .i& Cavfna. He
has a very fiti reaord in the medPoa1 aohool. He aid some &exdoal researoh
with I& tihipleg whioh was published ia the Journal of Biologioal Chemistry,
19241, llx, 237.  1 am eeadimg you a reprfat.  Umder the advfae of Dr. AIWS he
has applied for a medical internship h8rc and Aron! his mmord f shmld sag that
he will be pr&tirtsrlly uertaln to get ite  He seemed vesy Mach attraclrted by the
idea of the preUem oa &auoemia but he may deolds, toward taking a general i&
ternship firtat.  I think that he is a very able yoke mau fully worth brir@ng
Into re88arch far 8 perma5ent CBreer.  He will talg the matter over with Llrr &uos,
u&m he knum well and XeB me kmw this week whether he would seriously oonslder
Ita  on Saturday he goes hom to IndIanapolls and it ocours to me that he might
COF& back thrm@ 2%~ Pork to see yozl.

    I[ have a Jqmme, a Dr. Snguyama, seat here by the Japanese Government
to prepare Umaelf for a abir in Pathology in Japan. Ee crhoe8 of his own aaaord
to oome here end work in histology and embmolo,gy as a preparstion.  Fe have
bruught him Into our grmq LIP the blood mrk,  We   as hi%i own problem the dsvolop
S&%t Of the di28 ~~11% in the chick and is 8~~~ getting some r81Ult8e  2hea he,
joins us in the studies af the living blood cells in our experimental btnfmals. Ee
is really ableg his plan is to rptay here thla year and perhaps go to Gez~m4y next
year, but 3 think th&he might be very attracted by the idea of golug to the
Institute aext year,  Hia expense8 here are paid by the Jtipaneae Governmeat. 1
Jndge he has not a very Iargo grant bmauss he had to stay here a.21 80-r rather
thaa ~0 to a rrooler place,  31th 8 s&l1 additional grant to cover the i%~~.aed
living expenses fn Wew York, it OOORPS to me that he might be YS~J~ glad to go on
with the walk aaxt yew.  He took eoarses in Embryology at the University last
spring*

    Doring this f&U a Rmgprian, a Dr. George St. De -Xenyi, visited the
laboratory.  Ee had been a Xwkefeller Fellow and had spent B year with IIre Cbmbers
at Cornell, fn ISew York City.  oplc young Hungcr&m in the laboratory aaid that
Dr. iAeny$ iaaa quite the ablest young Anatomist In Rungsry.  Dr. Benyi ni@Ae a great
lmprerrlon on ~11 of us.  He would be veq glad to oome to America but by the
c3onditfon8 of his Fellowrehip he lrrust go bask to Eun@ry to teach this aoming year.
Ne is worth our   in& in wind becrerasa he is 8 very corogeteat m&80   f will f%Qd
out from Dr. Doan if there Is some one at Rarvr;rd and from We Richards if we oan
gee some oae irom PezmzgIvania.

    I till eend to %I=. Smith a general est&mate of equipmt for next yew
within a few days and will let you know at once th8 restzlt of w oonferentte 4th
Dr. Dosn.  Eze laight also stap to see you otl hire mp bak to Roeton after Chriatnmr~