Correspondence



31



It was through Mr. McGredy’s enthusiasm that I got interested

in aviculture, and there are many interested likewise through

coming in contact with him and seeing the love he had for all his

feathered friends.


He was always most anxious to give advice and assistance to

amateurs who asked for same. Personally, his generosity and

kindness to me, and I am one of many, are never to be forgotten.



CORRESPONDENCE, NOTES, ETC.


DANGER IN DUSTY SAND


Probably many of us have lost birds at times in circumstances which

baffle us. I had a case in point last year when a Parrot Finch died and the

post-mortem showed pneumonia.


Now this bird had been kept in an aviary the temperature of which

was thermostatically controlled at 60° F. and a maximum and minimum

thermometer was always in the aviary and showed that the temperature

had never been below this. It is a well constructed place, nicely ventilated

but definitely without any draughts. The bird had been in fine form for

quite a time. However could it get pneumonia ? And what could one do

more to prevent a recurrence ?


I venture to suggest that we often invite lung trouble in our birds by the

sand we use on the floors of cages and aviary shelters. Sand consists almost

entirely of silica, and it has been known for a long time that silica dust breathed

into the human lung has a most harmful effect and eventually proves fatal

through silicosis. In industries handling materials with a high silica content

very elaborate precautions are taken by means of ducts to draw away this

fine silica, dust, and compensation to the next of kin has to be paid for deaths

resulting from this cause.


The silica itself is not harmful, of course, unless it is in such fine particles

as to be carried about in the air and these fine particles are most easily air¬

borne when it is perfectly dry. Now one of the easiest ways of getting it

perfectly dry is to place a thin layer, as we do, on the aviary floor, and a

certain way of making sure that the silica dust does not lie there, but is wafted

into the air, is to have a number of small creatures with efficient winnowing

implements in the form of wings flying down on to it and rising up from it.


I am informed that in humans the complaint is not easy to distinguish

from the ordinary condition of tuberculosis ; with lungs as small as those of

a bird the task would perhaps be more difficult, or even impossible, but

Mr. Gray would perhaps kindly give us his opinion on this.


However, to avoid the risk certain precautions can be taken. One should

procure a 50-mesh sieve or riddle, and test in a perfectly hone dry state the

sand one uses with this (a 50-mesh sieve is one which has 50 apertures to

the linear inch). One can soon prove to one’s own satisfaction that any



