No 10

10 PM

Tuesday nite [sic.]

Darling,

Went thru a series of lectures to-day again - we get lectures on combat indoctrination, medical indoctrination (lecture in the various diseases we may contact in the various theatres) First aid (the importance of which knowledge is beginning to impress me with a new importance) Went thru' the pressure chamber again (to check sinuses, improper teeth fillings + of course further to familiarize one with his oxygen equipment + the various hazards one can encounter at high altitudes, thru' the lack of knowledge. The temperature at 30,000 ft (at which altitude most of the high altitude bombing is done) is in the neighborhood of 50 [[degree symbol]] below zero - every precaution must be taken at this temperature - frost bite being a serious menace - that's why we are being taught to do everything with gloves on. Frost bite of the fingers can occur within 30 seconds at that altitude + which in turn might force an amputation of said numbers