100 YEARS AGO

Messrs. D. Schulte and Co. have submitted a sample of their self-lighting Bunsen burner, in which the well known property of finely divided platinum igniting under the influence of a stream of hydrogen is employed. The burner proper is of the usual type, but is furnished with a byepass tube at the side, controlled by a cross stopcock. At the top of the byepass, close to the open end of the burner, there is fitted a small bracket holding the bundle of several fine platinum filaments, so constructed that the thin stream of gas from the byepass tube impinges on the stretched wires... The arrangement works very readily, and if the old difficulties with regard to the durability of the delicate portions can be surmounted, the apparatus should be of considerable convenience to laboratory workers.

ALSO

At a sale recently held by Mr. Stevens in King Street, Covent Garden, a great auk's egg in fine condition was sold for two hundred guineas... This is a considerable falling-off from the three hundred guineas obtained for the last specimen sold by Mr. Stevens, the reason being attributed to the fact that several other fine examples are in the market.

From Nature 26 May 1904.

50 YEARS AGO

It has been shown that as a rule the deoxyribonucleic acid content of the interphasic nuclei of tissues of a given species corresponds to a constant equilibrium value, which is double that of the deoxyribonucleic acid content of the spermatic nuclei of the same species. Consequently, at each mitotic division, synthesis of deoxyribonucleic acid must take place in order that the quantity of this substance should be restored in the nuclei of the daughter cells at a ‘normal’ level... According to some authors, this occurs immediately before mitosis, so that the content reaches double that of the normal value: after division each nucleus of the daughter cells receives also a normal content. According to other authors, synthesis occurs soon after mitotic division when nuclei of the daughter cells which receive only half of the normal content restore the latter. We have undertaken the study of this question in the thyroid cell of the white rat... These measurements show clearly that in our material deoxyribonucleic acid is synthesized immediately before the onset of mitosis.

From Nature 29 May 1954.