New theory and old practice in relation to medicine and certain industries : being an analysis of current literature of these subjects / by C.A. Gordon.

  • Gordon, Charles Alexander, 1821-1899.
Date:
1886
Catalogue details

Licence: Public Domain Mark

Credit: New theory and old practice in relation to medicine and certain industries : being an analysis of current literature of these subjects / by C.A. Gordon. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    however, the entire harvest was nearly lost by reason of inclemency of the weather, the whole quantity obtained being only a little over two millions of kilogrammes. [Here then, is a cause of failure, more calamitous than the pebrine had ever been.] From 1877 to 1882 the produce oscillated between four and eleven kilogrammes, (p. 95). M. Eondot gives in tabular form the purport of the above figures, and represents, as shown below, the average produce of cocoons in a series of periods beginning with 1865, namely, the year in which M. Pasteur began his investigations, [but when, as already observed, the use of the microscope was common in Italy.] It wiU be sufficient for pur- poses of comparison to give the whole number of milUons of kilogrammes, omitting minor quantities, thus : — From 1865 to 1867 ... 15. „ 1868 „ 1870 ... 9. „ 1871 „ 1873 ... 9. From 1874 to 1876 ... 7. „ 1877 „ 1879 ... 8. „ 1880 „ 1882 ... 8. From these statistics the fact is brouglit out that in no period has the produce equalled that of 1850. (p. 96.) [A very important fact con- sidering what is elsewhere asserted in regard to the results of M. Pas- teur's discoveries in having saved a great industry which was threatened with extinction.] Besides the method recommended by M. Pasteur of selecting healthy eggs, and the use of the microscope, the measure has been taken of re- introducing the race of cocoons from the department of A.rd^che, these being of the ancient Chinese race [and consequently naturalised to the conditions of climate, soil, and mulberry plant in France.] But, at pre- sent, cultivators have been unable [J^ote this] to preserve silk-worms from diseases which are often the consequence of luifavourable atmos- pheric conditions; it is also to be noticed that of late years the demand for silk has been less than formerly (jd. 98), and consequently the number of sericultors has diminished from 297,130 in 1868 to 165,617 in 1883. (p. 99.) More recently, notwithstanding that there have been fewer cultivators of silk-worms and fewer eggs placed for hatching, the yield of cocoons has increased, but in the varying proportions of 91 from 1875 to 1877, 70 from 1878 to 1880, and 104 in 1881-1882. (p. 100). At the same time that disease prevailed among silk-worms in France it prevailed also in the mulberry-trees, on the leaves of which the insects fed. [The food being vitiated, the health of creatures that had to live upon it naturally became vitiated also.] Within the past thii-ty years it