By the early 1 930s the science of statistics as An argument by analogy may elucidate the
we now know it was rapidly developing. point. Let it be supposed that many thou-Correlation …

of acute appendicitis, whose differ-ential count of 100 cells shows 70 per cent of
polymorphonuclears, and an hour later, 80 per cent. Isthis a significant change, or may it be …

* This work is part of an investigation into leuco-cyte size and number that is being
conducted with the aid of generous grants from the Banting Research Foundation, Toronto …

The method in general use for routine estimation of the erythrocyte content of the blood is to
dilute the specimen of blood in a calibrated pipet in the ratio of 1 to 200, and, after mixing, to …

In differential blood counting, one attempts by careful observationof a limited number of
leukocytes to obtain a picture of the actual distribution of the various types of cells in the …

This article is of fundamental importance and does not admit of abstract. Haematologists
should consult the original. The author begins with an historical sketch of the development of …

The value of 'Statistical control'in haematology has been demonstrated. After a short
historical survey of the chief contributions to the theory of the technique of counting and of …

= V18= 4.24 chance in only 1% and 0. 1% of cases respectively. In the above example the" t"
value was 3.5. This means that the observed differences would be ex-pected to occur in less …

1 The number of red blood corpuscles does not keep constant in the same individual, but
varies from day to day. 2 The greatest variation may reach 2.4 million. The greatest variation …

The errors made in the use of a haemocytometer and those occurring in the making of a.
differential count are discussed. In the former group, apart from errors due to carelessness or …